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PLN20180067 Staff Report with AttachmentsCITY OF EDMONDS l-21 5th Avenue North, Edmonds WA 98020 Phone: 425.771*0220 . Fax: 425.77I.0221 . Web:www.edmondswa.sov DEVELOPM ENT SERVICES DEPARTM ENT . PLAN N I NG DIVISION c. 1 s9o Project: File Number: Date of Report: Reviewed By: PLANNING DIVISION PRELIMINARY SHORT PLAT REVIEW FINDINGS, CONCLUSIONT & DECISION Howell LLC Two-Lot Unit Lot Short Subdivision P1N20180067 2019 t) t¡. en Lien, En mental Programs Manager SUMMARY OF PROPOSED ACTION The applicant is proposing a two-lot unit lot subdivision on a property with a recently constructed duplex. The unit lot subdivision will place a property line in the centerline of the party wall separating the two dwellings units so the each unit will be on a separate lot. The subject property was zoned RM-2.4 (multi-family residential; one dwelling unit per 2,400 square feet of lot area) under contract rezone R-95-L77 - GENERAL INFORMATION A. Application L. Owner: 318 Howell LLC 2. Applicant: 318 Howell LLC 3. Site Location: 318 Howell Way (Tax lD 00409600101902) 4. Request: To divide one parent lot with a total area of 7,43O sq. ft. (0.17 acres) into two unit lots. 5. Review Process: Short plats are Type ll decisions pursuant to ECDC 20.01.003. Following a public comment period, the Director (or designee) makes an ad ministrative decision. 6. Attachments 1) Land use application 2) Applicant Cover letter 3) Preliminary Short Plat Map 4l Civil as-built drawings 5) Stormwater Plan (approved under BLD20i.70B8Z) 6) Building Plans 7) Zoning and Vicinity Map 8) Building Division Comments 9) Engineering Memorandum of Compliance and Conditions of Development 10) Public notice documentation 11)Ordinance No. 3070 - Contract Rezone R-95-177 III. FINDINGS OF FACT AND CONCLUSIONS A. Setting The subject property and two adjacent properties (east and south) were rezoned R.M-2.4 under contract rezone P,-95-177. The surrounCing propertics are a mixed of single-family (RS-6) and multi-family (RM-2.4) zoning and developed with single- family residences and multi-family structures. City Park is one block to the west and commercial development in the BD3 zone is one block to the east. B. EnvironmentalAssessment 7. Critical Area: The subject property was reviewed and inspected for critical areas as defined by ECDC 23.40 under CR420170093. lt was determined that the site does not contain any critical areas and so a waiver from further critical area study was granted. 2. Shoreline: The subject property is not located within shoreline jurisdiction. 3. SEPA: Review under the State Environmental Policy Act (SEPA) is not required for a short plat pursuant to WAC 197-1L-800(6Xd) - Land use decisions. C. Comments 1. Technical Comments ln addition to the Planning Division, this project was reviewed by the Building and Engineering Divisions. The Building Division indicated that for the buildings that have already been constructed, the new property lines will need to be located in the center of the existing party walls between dwelling units, and verified by recorded survey (Attachment 8). This is a requirement for final unit lot plat submittal per ECDC 20.75.045.J. The legal descriptions for the new lots note the property line between the units will be the centerline of the party wall in the existing building. The Engineering Division has noted the proposed plat indicates general engineering feasibility (Attachment 9). Howell LLC Preliminary Unit Lot Short Plat File No. P1N20180067 Page2 of t2 2. Public Notice and Comment ECDC Chapter 20.03 provides the City's regulations for public notice of development applications. A "Notice of Application" dated December 28,20L8 with a comment period running through January tL, 2OL9 was posted at the subject site, Public Safety Complex, Development Services Department, and Library on December 28,20L8. The notice was also published in the Herald Newspaper and mailed to property owners within 300 feet of the site on December 28,2078 using a mailing list provided by the applicant. Documentation of compliance with the public notice requirements is included as Attachment 10. The City has complied with the public notice requirements of ECDC 20.03. No written public comments were received during review of the subject proposal. D. ECDC 20.75.045 Unit Lot Subdivision To allow for the creation of fee simple (unit) lots for townhouses and similar ground- based dwelling units, a provision was recently added to the Edmonds Community Development Code (ECDC). Staff's findings regarding ECDC 20.75.045 are provided below. L Purpose. The unit lot subdivision process provides opportunities for dividing fee simple ownership of lond to create townhouses, rowhouses and similar fee-owned dwelling units as an olternotive to both condominium ownership and traditional single-fomily detached subdivision. IJnit lot subdivisions determine complionce with the relevant dimensional stondards of ECDC Title 1-6 by onolyzing whether the porent lot complies, but not requiring thot each newly creoted lot within the unit lot subdivision (the unit lot) complies, with those dimensional stondards. A unit lot subdivision does not permit uses or densities thot ore not otherwise allowed in the zoning district in which the unit lot subdivision is proposed' As described in the following sections, the proposed preliminary short plat meets the purposes of the unit lot standards. 2. Appticabitity. The provisions of this section opply exclusively to the subdivision of lond for single-family dwelling units, townhouse, ond rowhouses ond moy be apptied only in the following zones: multiple residentiol, general commerciol, and Westgote mixed-use. A single lot within a unit lot subdivision may contoin multiple dwelling units when the unit lot contains oll such dwelling units within one building. Flats are permitted os on element of a unit lot subdivision only when ø single lot within a unit lot subdivision contains the entire building in which flats ore located. The subject site is zoned multi-family (RM-2.a) and a two-unit townhouse type development is located on the subject property (Attachment 6). The proposed lot line willfallon the centerline of the common wallwithin the building (Attachment 3). No flats are proposed, as can be seen on the approved plan sheets from the Howell LLC Preliminary Un¡t Lot Short Plat File No. P1N201,80067 Page 3 of 12 assoc¡ated building permits (Attachment 6). Each of the dwelling units is vertically aligned with two levels of living space. 3. Association with Site Development - Application Timing. tn the cose of o vacont lot or o redevelopment site, o preliminary unit lot subdivision can only be submitted in coniunction with or subsequent to o development site plan as required by chopter 20.1-0, 20.1-1-, or 20.L2 EcDc, or in the cose desuibed in E1DC 20.L0.020(8)(3) submitted in conjunction with or subsequent to ø building permit. The building on the site is a duplex which is exempt from design review pursuant to ECDC 20.010.020.8.3. The duplex was reviewed and approved by staff under 81D20170882. 81D20170882 was applied for on June 29, 2OL7 and received a certificate of occupancy on April 8,2019. The preliminary short plat application was submitted on November 27,20L8. 4. Conformance with Standards of the Porent Lot. The porent lot must comply with ond is vested to the applicoble development standards (ECDC 20.75.030(E)) in effect ot the time a complete opplication for preliminary unit lot subdivision is ctthmì++a,J ^ê ^ -^-,,1+ ^l+L^ ,,^:t t^+ -,,LJ:.,:-:^^ LL^ :^J!..:J..-, ...-lL t-L- ...!Lr- !.- L,- -ruurrrrL.cu. ^r u rcJu,LvJ Lttt urt,L ruLSuuurvrS,uIt, Llte rltutvluuul unlL lQLS wltriln tng subdivision may be nonconforming with respect to the butk ond dimensional standords required by ECDC Title 76. As with dimensional stondords, compliance with access stondards, including but not limited to fire lones, drive aisles, turn-arounds, ond occess of/to the parent lot from/to the street will be evaluated bøsed on the porent lot's compliønce with such requirements, ond not based on whether individual unit lots meet such stondords. The subject property is located in the RM-2.4 Multi-Fam¡ly Residential zone and is subject to the requirements of Chapter 16.30 ECDC. As noted above the property was rezoned to RM-2.4 under contract rezone R-95-L77 (Attachment 1L). Contract rezones place additional restrictions on properties beyond that allowed by the under lying zoning. Development standards for the RM-2.4 zone are as contained in ECDC 16.30.030. Those standards marked with a * where conditions ofthe contract rezone: Zone Minimum Lot Area per Dwelling Unit* Minimum Street Setback2 Minimum Side Setback2 Minimum Rear Setback Maximum Height* Maximum Coverage RM-2.4 Max 2 per units per lot 15',10'ls',25',45% 2 RS setbacks may be used for single-family homes on lots of 10,000 square feet or less in all RM zones. Setbacks: The structure on the property complies with the setbacks of the parent lot (Attachment 3) being L5 feet from the dedication line on the north (street Howell LLC Preliminary Unit Lot Short Plat File No. P1N20180067 Page 4 of L2 setback), 10 feet from the east and west property lines (side setbacks) and 16.8 feet from the southern property line (rear setback). Height: The structure was constructed to 25 feet in height from average grade as required by the contract rezone (Attachment 3). Coverage: The structure on the property covers 3208 square feet, which is 45% of the lot area following the S-foot street dedication. 5. Future Additions ond Modifications. Subsequent platting octions, odditions or modificotions to the structure(s) may not create or increose ony nonconformity of the parcel lot. Changes requiring permitting that affect only the interior of building units will be evaluoted for complionce with the requirements only for that unit. Any exterior chonges witl be evoluated for compliance by considering whether the porent lot would still comply with applicable development standords. Any opplicotion for such external chønges will require outhorizotion of oll owners of affected unit lots or approval of the HOA where changes to commonly owned trocts are proposed. Documentation describing how additions and modifications are managed by the homeowners' association created for the project will be required with the submittalof the associated final plat. 6. Homeowners' Association Ownership of Common Areas. Any commonly used oreas or facilities within o unit lot subdivision, including but not limited to common access, gorøge or parking oreos, common open spoce or recreation spoce, common courtyards, commonly used stormwater facilities or side sewers and other similor features, must be owned and mointoined by a homeowners' ossociøtion with the right to øssess the individuol unit lot owners os necessary to properly maintoin ond repoir such oreos. Appropriote documentation regarding the rights of the homeowners associotion must be submitted for recording with the finol plat. Documentation describing the homeowners' association will be required with the submittal of the final plat for the project. 7. Mointenonce Agreements for Building Exteriors. Mointenance ogreements must be executed and recorded as an element of the finol unit subdivision plat or short ptat for mointenonce of all building exteriors except in cases where oll dwelling units ore detoched. The mointenonce ogreement must require equol participation by att owners within ony one building and must be recorded on the finol unit lot plat. The requirement does not apply to detoched single family dwelling units. Common wall construction must meet currently odopted building codes. Because the dwelling units are attached in this instance, maintenance agreements for building exteriors will be required with the submittal of the final plat for the project. Howell LLC Preliminary Unit Lot Short Plat File No. P1N20180067 Page 5 of 12 8. Parking on Different IJnit Lots Allowed. Within the parent lot, required parking for o dwelling unit moy be provided on o different unit lot thon the lot with the dwelling unit øs long as the right to use thot parking is formolized by an eosement on the finol plat. Parking: Condition 2.3 of the contract rezone noted that each unit shall have its own parking facility provided on-site (Attachment 11). Each dwelling unit in this unit lot subdivision has its own two car garage. 9. Notice of Unit Lot on the Final Plot. The fact that the unit lot is not o separote buildoble lot ond thot additional development of the individuol unit lots may be limited os o result of the opplication of development stondards to the parent lot must be noted on the final plat. A note to this effect must be added to the face of the final plat for the project. LO. An applicotion for finol unit lot plot will not be accepted until oll foundotions, including common woll foundations, øre instolled and located on the foce of the finol plat by the land surveyor of record. The building was recently completed and granted certificate of occupancy on April 8, 2019. The application for final plat may be submitted at any time after the approval of the preliminary plat. I1'. Review. Unit lot subdivisions of four or fewer lots ore processed ond reviewed os short subdivisions while five or more lots are formal subdivisions pursuant to Chapter 20.01 ECDC ond the requirements of this chapter. This unit lot subdivision will create only two lots as such, is being process as a Type ll decisions pursuant to ECDC 20.01.003. Following a public comment period, the Director (or designee) makes an administrative decision. E. ECDC 20.75.080 General Findings A proposed subdivision may only be approved if all the general findings listed in ECDC 20.75.080 can be made for the proposal as approved or as conditionally approved. Staff's findings in regard to ECDC 20.75.080 are described below. L Subdivision Ordinance. The proposol is consistent the purposes of this chopter (ECDC 20.75) and meets all requirements of this chapter. The proposed unit lot subdivision is consistent with Sections 20.75.020 and 20.75.045.A and 045.8 ECDC. Because the site has already been redeveloped as approved under 81D20170882, the proposed subdivision will not negatively impact public health, safety or general welfare, will not negatively impact congestion on streets and highways, has adequate access to water, utilities, sewerage, storm drainage and provides proper ingress and egress and will be uniformly monumented. Howell LLC Preliminary Unit Lot Short Plat File No. P1N20180067 Page 6 of 12 2. Comprehensive Plan. The proposal is consistent with the provisions of the Edmonds Comprehensive Plon, or other adopted city policy, ond is in the public interest. The Comprehensive Plan designation for this site is "Multi Fomily - High Density" within the "Downtown Activity Center". Applicable goals, objectives and policies in the 2018 Comprehensive Plan include: Sustainobility Gool G Develop housing policies, progroms, ond regulotions designed to support and promote sustainability. Support ond encourage a mix of housing types and styles which provide people with afÍordable housing choices geored to changes in life style. Dow ntow n/W ote rfro nt Goo I A.6 Provide greøter residential opportunities and personal services within the downtown, especiolly to accommodote the needs of o chonging populøtion. Housing Godl G Provide housing opportunities within Activity Centers consistent with the lond use, tronsportotion, ond economic goals of the Comprehensive Plan. G.L. Promote development within Activity Centers that supports the centers' economic octivities and transit service. G.l..b. Plan for housing that is locoted with eosy occess to tronsit and economic activities that provide jobs ond shopping opportunities. Residentiol Gool A High quatity residential development which is oppropriote to the diverse lifestyle of Edmonds residents shoutd be møintoined and promoted. The options availoble to the City to influence the quality of housing for all citizens should be opprooched realisticolly in balancing economic, social, aesthetic and environmentol considerotions. Residentiol Goal B A broad range of housing types and densities should be encouraged in order thot a choice of housing witl be avoilable to oll Edmonds residents, in accordance with the fol lowi n g pol i cies : 8.2 Muttipte. The City's development policies encouroge sustainable high quality site and buitding design to promote coordinated development and to preserve the trees, topography and other notural features of the site. Stereotyped, boxy multiple unit residential (RM) buildings ore to be ovoided. The proposed unit lot plat will create additional home ownership opportunities within the City of Edmonds. The unit lot sites should be relatively more affordable than traditional single family development, however, because the parcels and dwelling units are smaller. While the site could be platted through the Howell LLC Preliminary Unit Lot Short Plat File No. P1N20180067 PageT of 12 condomin¡um process (which the City does not review), the City is able to review the unit lot subdivision and related maintenance agreements and homeowners' association documents to ensure that future maintenance of the development is appropriately addressed. The overall proposal should not cause any adverse impacts and appears to be consistent with the residential development goals and policies of the Comprehensive Plan. Therefore, staff finds that the proposal is consistent with the Comprehensive Plan and is in the public interest. 3. Zoning Ordinance. The proposøl meets all requirements of the zoning ordinance, or a modification hos been opproved os provided for in this chapter. The subject property is located within the RM-2.4 zone and subject to additional restrictions under contract rezone R-95-t77. Refer to Section lll.D.4 of this report for an analysis of the proposal's compliance with the applicable zoning standards. The proposal meets allof the requirements of the RM-2.4 zone and the conditions of contract rezone R-95-L77. 4. Flood Plain Management. The proposol meets all requirements of the Edmonds Community Development code relating to flood pløin monagement. The proposed project is not located within a designated flood plain management area. F. ECDC 20.75.085 - Review Criteria. Pursuant to ECDC 20.75.085, the following criteria shall be used to review proposed subdivisions: 1. Environmental. o. Where environmental resources existing, such os trees, streams, ravines or wildlife habitats, the proposal sholl be designed to minimize significant odverse impacts to resources. Permanent restrictions may be imposed on the proposol to ovoid impact. b. The proposal sholl be designed to minimize grading by using shared drivewoys and by reloting street, house site and lot placement to the existing topography.c. Where conditions exist which could be hazordous to the future residents of the lond to be divided, or to neorby residents or property, such os ftood ploins, steep slopes or unstoble soil or geologic conditions, a subdivision of the hozordous lond sholl be denied unless the condition can be permonently corrected, consistent with parographs A(J.) ond (2) of this section.d. The proposal shall be designed to minimize off-site impacts on drainoge, views and so forth. There will be no change to the existing buildings and site improvements through this unit lot plat so there will be no additional environmental impacts. 2. Lot ond Street Layout. Howell LLC Preliminary Unit Lot Short Plat File No. P1N20180067 Page 8 of 12 a. Lots sholl be designed to contoin a usable building areo. lf the building oreo would be difficult to develop, the lot shall be redesigned or eliminoted, unless speciol conditions can be imposed on the approval which will ensure thot the lot is developed properly. Each of the proposed unit lots will contain one of the existing dwelling units and a small private yard. b. Lots shall not front on highwoys, orteriols or collector streets unless there is no other feosible access. Special occess provisions, such os shored drivewoys, turnarounds or frontage streets moy be required to minimize traffic hazards. Each dwelling unit fronts an alley which connects with Howell Way which is not a highway, arterial or collector street. c. Each lot shall meet the applicable dimensional requirements of the zoning ordinance. Since this is a unit lot plat, the parent lot must comply with the development standards for the zone but the individual unit lots do not. The subject property is located within the RM-2.4 zone and subject to additional restrictions under contract rezone R-95-L77. Refer to Section lll.D.4 of this report for an analysis of the proposal's compliance with the applicable zoning standards. The proposal meets allof the requirements of the RM-2.4 zone and the conditions of contract rezone R-95-I77. d. Pedestrian wolks or bicycle poths sholl be provided to serve schools, parks, pubtic facilities, shorelines ond streams where street access is not adequote. Citywide efforts to provide safe transportation include enforcement of traffic regulations, provision of crosswalk and sidewalks for pedestrians, and provision of well-designed streets for safe driving. Safety also involves ongoing coordination with emergency service providers to ensure access for their emergency equipment. Recommendations to address safety issues are based on assessment of historical collision data, focused sub-area or corridor safety studies, or on citizen feedback. The City of Edmonds applies a Walkway Prioritization Process provided in the Transportation Element of the Comprehensive Plan in assessing where sidewalks should be required or upgraded. Criteria has been developed to evaluate and prioritize walkway improvement projects. These criteria (which include distance from schools) are used to prioritize improvements to walkway sections that are identified based on input from public meetings, Walkway Committee meetings, and deficiencies determined from a review of the existing city walkway inventory. The criteria are weighted according to their importance. A system of points evaluate each proposed project against each criterion. The result is a weighted average score that helps to compare and prioritize proposed projects. The City's policy is to consider these criteria in Howell LLC Preliminary Unit Lot Short Plat File No. P1N20180067 Page 9 of 12 conjunction with City code and the Sidewalk Comprehensive Plan Map in determining sidewalk requirements for subdivisions. New sidewalks were installed along the Howell Way frontage in association with the development approved under building permit BLD2OI7OBB2. 3. Dedicotions a. The city council may require dedicotion of lond in the proposed subdivision for public use. b. Only the city council may approve o dedication of park lond to sotisfy the requirements of ECDC 20.75.090. The council moy request a review and written recommendotion from the plonning advisory board. c. Any opprovol of a subdivision shall be conditioned on appropriate dedication of land for streets, including those on the official street mop and the preliminory plot. Per the City Engineering Division requirements (Attachment 9), a S-foot street cieciication is required along Howell Way. See Section lll.G below regarding the dedication of park land. 4. lmprovements. o. lmprovements which moy be required, but dre not limited to, streets, curbs, pedestrion wolks and bicycle pøths, sidewalks, street landscaping, water lines, sewage systems, droinoge systems and underground utilities. b. The person or body øpproving a subdivision sholl determine the improvements necessory to meet the purposes ond requirements of this chapter, ond the requirements of: i. ECDC Title 78, Public Works Requirements; ii. Chapter 1"9.75, Fire Code, as to fire hydrants, wøter supply and occess. This determination shall be bosed on the recommendotions of the community development director, the public works director, and the fire chief . All improvements at the site were reviewed and approved by appropriate staff at the building permit stage. No additional improvements are required for the unit lot plat. c. The use of septic systems may be approved if all of the fotlowing conditions are met: i. lt is more than 200 feet, multiplied by the number of lots in the proposed subdivision, from the nearest public sewer moin to the nearest boundory of the land to be divided. ii. The lond to be divided is zoned RS-20. Howell LLC Preliminary Unit Lot Short Plat File No. P1N20180067 Page 10 of 12 tv. Howell LLC Preliminary Unit Lot Short Plat File No. P1N20180067 Page LL of t2 iii. The pubtic works director ond city health officer determine that soil, drainage ond slope conditions are satisfactory for septic use and that all requirements of WAC 248-96-090 ore met. There are no septic systems included as part of the proposed project. 5. Flood Ploin Monagement. All subdivisions shall comply with the criterio set forth in the Edmonds community Development code for flood plain manogement. The subject property is not located within a Flood Plain Management area. G. ECDC 20.75.090 - Park Land Dedication. According to ECDC 2OJ509O, before or concurrent with the approval of the final plat of any subdivision, the subdivider shall dedicate land, pay a fee in-lieu of dedication, or do a combination of both, for park and recreational purposes. With the adoption of Ordinance 3934 in 20L3, park impacts are now addressed through the assessment of park impact fees in accordance with Edmonds City Code (ECC) Chapter 3.36. Park impact fees were assessed with building permit 81D2017882 at the time of permit issuance. STAFF RECOMMENDATION ON SUBDIVISION Based upon the Findings of Fact, Conclusions, and Attachments to this staff report, the application for a two-lot unit lot short plat on the property located at 3L8 Howell Way is APPROVED subject to the following conditions: L Prior to recording, the applicant must complete the following requirements: a. Make the following revisions to the short plat: i. Add: "Conditions of approval must be met and can be found in the approval for the subdivision located in File No. PLN2017OO4L in the City of Edmonds Planning Division." ¡¡. Add the following note: "A unit lot is not a separate buildable lot and additional development of the individual unit lots may be limited as a result of the application of development standards to the parent lot." ¡i¡. Add the addresses for the new lots as follows: (a) Lot A - 314 Howell WaY (b) Lot B - 318 Howell Way iv. lnclude on the plat all required information, including owner's certification, hold harmless agreement, as well as the Development Services, Public Works, and Mayor's approval blocks' b. Submit draft homeowners' association documentation including requirements for future additions and modification, and the maintenance of building exteriors. c. Consistent with the City's Official Street Map, a five foot street dedication to the City of Edmonds is required along the property frontage on Howell Way. V d. Make sure all documents to be recorded meet the Snohomish County Auditor's requirements for recording. 2. Submit an updated copy of the title report with the documents proposed to be recorded. The title report must be prepared within 30 days of submittal for final review. 3. Submit two copies of the plan sheets to be recorded for City review and approval. Once approved, the City Clerk will record the documents at the Snohomish County Auditor's office. APPEAL Pursuant to ECDC 20.O7.O04, a party of record may submit a written appeal of a Type ll decision within L4 days after the date of issuance of the decision. The appeal would be heard at an open record public hearing before the Hearing Examiner according to the requirements of Chapter 20.06 ECDC and ECDC 20.07.004. VI. LAPSE OF APPROVAT ECDC 20.75.100.B states, "Approval of a short plat shall expire and have no further validity at the end of seven years if preliminary short plat approval is issued on or before December 3!,2013, and five years if preliminary short plat approval is issued on or after January L, 2Oi-4, unless the applicant has acquired final short plat approval within the specified time period." Since preliminary approval has been after January I,2OL4,this preliminary short plat approval shall be valid for five years from the date of this staff report. VII. NOTICE TO COUNTY ASSESSOR The property owner may, as a result of the decision rendered by the hearing examiner, request a change in the valuation of the property by the Snohomish County Assessor's Office. VIII. PARTIES OF RECORD City of Edmonds 121- 5th Avenue North Edmonds, WA 98020 Howell LLC Preliminary Unit Lot Short Plat File No. P1N20180067 Page t2 of t2 318 Howell LLC 7305 Soundview Drive Edmonds, WA 98026 City of Edmonds Land Use Application odrv tllZl lt8 REç'DBY rw 4L,4Ll RECEPT# HBenrNaDnre rl HE N STAFF T] PB D ADB D CC Fß,8#?LNLoß6b7 zowr. ?-uh 7.4 bs-sr> Í n ü ü tr gl n ü L n L tr rì ARCHITECTURAL DESIGN REVIEW CoNæRElüNsIvE PLAN AtvßNDNfENT Cotnrrto¡rer Use PsRr4r HorvE Occi-rPATloN FORMAL SUBDIVISIoN Suont SusorvrsroN Lor LrNe AorusrMENT PLANNED RESDENÏAL DEVELOPNßNT ^mr^,^t C'!ÐñTf,l¡ñ ^!ñrñr¡T¡¡'Tvf rturu ù]lwr lv¡ff ruvÉt\urvEt\ I STREETVACATToN REZoNE SHORBLTNE PER\4rr VARIANCE / REASoNABLE USE EXCEPTION Orrun:2 Lot unit lot development . h,EASE NOTE TTTAT ALL INFqRMATIqN C0NTAINED WITHIN THE APPI;ICATION IS A PUBT.IC RECORD . PRoPERTY ADDRESS oR LocATIoN 318 Ho\¡r¡ellWây PRoJEcr NAN{E (Ix'ApprrcABLE) 318 Howêll l¡ìlay pROpDRTy OWNER 318 Ho\ ê¡l LLC pT{ONE # ã)6-S0-24¡15 ADDRESS 7305 Soundv¡ew Dr¡ve, Edtnonds, WA g)2Ê rwm¡chel@nwl¡nk.com Fax# TAXAccoUNT#oo¿logqþfiOl9()2 sec. Æ .rwP. 27n RNc. 3e DEScRrprroN oF PRorEcr oR koposED UsE (AT:tAcH covERLETTER As NECESSARY Short Subdivision - unit lot development DESCRIBE How rIrE PROJECT MEETS AppLIcABLE coDES (ATTACH covER LETTER As NECESSARY Sêe ettechêd Cove¡ Lettêr APPLICA¡.IT 318 Howell LLC PHoNe#206€30-2445 ADDRESS 7305 Soundview Dr¡ve, Edmonds, WA 98026 E-MArt-rwmichelt@nwl¡nk.com FAx# CorvTAcT PERS9N/AçE¡.{T Robin Michel PHg¡p f 206€30-2445 ADDRESS 7305 Soundv¡eì,v Dr¡ve, Edmonds, WA 98026 E-MAn.rwmichel@nwlink.com Fex# The undersigned applioan! and his/her/its heirs, and assigns, in consideration on the prooessing of the application agrees !o releaso, indemnifo, defend and hold the City of Edmonds harmless from any and all damages, including ¡easonabls atúomey's fees, arising from any action or infraotion based in wholo or part upon falsg misloading, inaoourate or inoomplete information firrnished by the applioant, his/herlits agents or employees. By my signature, I certi& that the information and exhibils hcrewith submitted are true and correot to the best of my knowledge and that I am authorized l,o file this apolication-er¡ the behalfofthç ownerøs listed below. srcNArLrREoFAppL *^*,o.r* /trn / 4 ñ'â'-( ,^*11t26nB Property Owner's Authorization I,Robin Michel certifu under the penalty of perjury under the laws of the Stste of lVashington that the following is a true oofi€ot statement: I have authorized the above Applioant/Agent to apply for the subjoct land use applioation, and grant my permission for the public offroials and the staff of the City of Edmonds to enter the subject property for the purposes of inspection and posting attendant to this applioation. STGNATURE oF OWNER 4¿4 ãa¿11t2d1A Questions? Call ( 425) 7 7 l -O22O. DATE Revised on 8/22/12 B - Land Use Application Page I of 1Attachment 1 Cover Letter 318 Howell LLC Short Subdivision 318 Howell Way ffiECEBWffiftr l{tV 2'r ?ri:J tlEVl¡-ûPMËNT SFIìVir,t:. C0Uf\¡Tt:n The proposed short subdivision meets or exceeds the requirements of the City of Edmonds Community Development Code (ECDC) as per the following code sections ECDC 16.10 Residential Zones - Purposes ECDC 16.20 RM - Multiple Family Residential Zone ECDC 18.00 Public Works Requirements ECDC 20.01Types of Development Project Permits ECDC 20.02 Development Project Permit Applications ECDC 20.03 Public Notice Requirements ECDC 20.7 5 Subdivisions ECDC 20.75.085 Subdivision Review Criteria ECDC 23.40 Environmentally Critical Areas The proposed short subdivision meets or exceeds the requirements of the City of Edmonds Comprehensive Plan as per the following sections: Residential Development A. Goals: 41. - 46. The proposed development is a custom design that harmonizes with the surroundings adding to the community identity and desirability. Minimizes view encroachment with a height limit of 25 feet. Project meets all city requirements for Planning Engineering and Building. B.2 Proposal meets or exceeds goals for multi-family development including massing, height and light. Attachment 2 SURVEYOR'S CERTIFICATE DECLARATION AND DEDICATION OF UNIT LOT SUBDIVISION NEW LOT LEGAL DESCRIPTIONS EXISTING PARCEL HOLD HARMLESS AGREEMENT UNIT LOT SUBDIVISION PLN20180067 CITY OF EDMONDS SNOHOMISH COUNTY, WASHINGTON APPROVALS DIRECTOR OF PUBLIC WORKS DEVELOPMENT SERVICES DIRECTOR 318 HOWELL LLC UNIT LOT SUBDIVISION PLN20180067 NE 1/4, NE 1/4, SEC. 26, T. 27N, R. 3E, W.M. ACKNOWLEDGEMENTS C & C Surveying LLC 4509 243rd PL SW (425)673-7502 (206)523-1654 Mountlake Terrace, WA 98043 AUDITOR'S CERTIFICATE TREASURER'S CERTIFICATE CONDITION OF APPROVAL NOTE PLAT MONUMENTATION NOTE STORMWATER MAINTENANCE AGREEMENT STORMWATER EASEMENT PROVISIONS EASEMENT TO THE CITY OF EDMONDS FOR INSPECTION OF THE STORMWATER MANAGEMENT SYSTEM PRELIMINARY Attachment 3 GAS DISTRIBUTION EASEMENT AND MAINTENANCE PROVISIONS UNIT LOT SUBDIVISION PLN20180067 CITY OF EDMONDS SNOHOMISH COUNTY, WASHINGTON 318 HOWELL LLC UNIT LOT SUBDIVISION PLN20180067 NE 1/4, NE 1/4, SEC. 26, T. 27N, R. 3E, W.M.C & C Surveying LLC 4509 243rd PL SW (425)673-7502 (206)523-1654 Mountlake Terrace, WA 98043 PRELIMINARY ELECTRIC DISTRIBUTION EASEMENT AND MAINTENANCE PROVISIONS SANITARY SIDE SEWER EASEMENT AND MAINTENANCE PROVISIONS WATER EASEMENT AND MAINTENANCE PROVISIONS Attachment 3 C & C Surveying LLC 4509 243rd PL SW (425)673-7502 (206)523-1654 Mountlake Terrace, WA 98043 SURVEYOR'S NOTES LOT A LOT B HOWELL WAY 4TH AVENUE SOUTH318 HOWELL LLC UNIT LOT SUBDIVISION PLN20180067 NE 1/4, NE 1/4, SEC. 26, T. 27N, R. 3E, W.M. PRELIMINARY Attachment 3 COVEREDPATIO471.82 ft 225.00'5.00'22.00'ALLEY SIDEWALK HOWELL WAY N60.00 FT 118.75 FT FT1' = 10' - 0"15'86'11"16'10"60.00 FT 40'6"BUILDING COVERAGE: 3208.5 SQ. FT.COVEREDPATIO1604.34 ft 2 PLOT PLAN DRIVE DRIVE MH P 101.2 102.8 102.7 GARAGE GARAGE 3'6" 3' 3' 7'4"10'5'3"3'3"14'6" 1'4" 1'4"6" PVC TIGHTLINE Key 6" GASKETED PVC SEWER LINE 3" POWER CONDUIT 4" YELLOW PVC GAS CONDUIT 4" PVC STORM TIGHTLINE 1-1/4" POLY WATER SERVICE LINE P G G G S S S P P P MH MH STORM MODULESCB CB CB SEWER CLEANOUT EXIS. 12" PSD EXIS. 8" CONCRETE PSS EXIS. 8" CONCRETE PSS EXIS. 12" PSD EXIS. 12" PSD 6'YD P P (2) 2" COMMUNICATION CONDUIT GASP RIM: 98.92 IE 12" S: 94.14 RIM: 99.75 IE 12" W: 95.00 IE 12" E: 94.50 IE 6" S: 94.75 RISER: 98.00 RIM: 98.97 IE 12" S: 94.93 IE 12" N: 94.93 IE 12" E: 94.97 RIM: 99.06 IE 12" E: 95.50 RIM: 99.21 IE 12" W: 95.25 IE 6" N: 95.24 IE 97.01 RIM: 100.25 IE 4" S: 98.21 RIM: 101.67 IE 6" 97.19 IE: 98.91 IE: 98.97 IE: 98.67 4" PERFORATED FOOTING DRAIN 4" GASKETED PVC SEWER LINE 4" PERF FOOTING DRAIN (2) 2" COM LINES G P S MICHEL DESIGN REVISIONS: 318 Howell, LLC. 7305 SOUNDVIEW DRIVE EDMONDS, WA 98026 DATE PRINTED: 4/15/19 PO BOX 1215 LYNNWOOD, WA 98046 DRAWN BY: ROBIN W. MICHEL PHONE: 206-930-2445 EMAIL: RWMICHEL@NWLINK.COM PROJECT ADDRESS: 318 HOWELL WAY EDMONDS, WA 98020 Property owners name:WMWM4/15/19 Attachment 4 CITY COPY þr-pzof'D887 RESUB JAN I I 20t8 %FFe6¡gqf* ¡ NSS{¡t{f S}l#ih¡f çs tÈd{è ç$, Åppåicaru*: Iì"egenI Const¡uclio¡: Inc 226241051r'Ave li Ëdmc ncl s - :¿,*,4. -ç I 02 {) STC}ÍI.MTV.{Tä}A STTH F g,ÀN For }TGWNLL lV.{Y ËÐMONÐS Prepared f*r T'he City olFlclmands 1?1 sfh "{r,e N Ëdmon¿ls, $'A qStX) 425-771-022{' Fro.i*ct Sifs l,r¡cation; 318 Horvell Wa-v ficlnio:rds. WA -?8{i2ü-41 18 T*x ld: Cr04ü96ûill 01çû2 mCû Pn'oject: l7-û852 Certi$ed Erosi*n änd SedimentE¡tion Control Leacl: Ta bi) named bv c*nlra*ttlr Stormw¿rter Site Plan Prepared Sy: .lacob D. Mealev. P.E. C0IVIPLIËS WITIT APPLICABLË CITY STO Ccnf*cf: tilclû F.O. Box 1478 ì-..r¡ereft, WA1r8:0ó 4:5-3û3-93ð3 CO E I * rrr - i?I lL/ | r I' $torrnx'al*r Sitc Plan llreparation Date Jun* 1.2ü17 Saúe R*vised: January* S,2{i1? Apprax irrrate Cc]üsû'ucticn I Jate : May tr,2û.l8 n:.û ßr:x 1,tT8 nãvereti, W.{*Sãû6t F}: 425^3û}.*}&3 F: 4?S,3ü3.93S? " infr:@i*xiühl*ngineering.n*t Attachment 5 TABLE OF'CONTENTS 1.0 Executive Summ4ry...................... 1.1 Minimum Requirernents Summary.... 2.0 Existing Conditions................. 3-0 ûffsite Analvsis 3.1 Upstream Analysis 3.2 Downstream Analysis ...... 4.0 Developed Conditions 5.0 Site Hydraulic Analysis 5.1 Existing Basin Summary.. 5.2 Developed Basin Summaly... 5.3 Frontage Basin Summary 5.4 Water Quality ..3 ',7 10 l4 14 l4 t6 """""17 ..............1 8 ..............1 8 ...........33 6.0 4ppendix.................... '.,,,,,,'37 .........38 Figures Figure 1 - Vicinity Map.......... ........6 Figure 2 - Soil M4p.......... .............11 Figure 3 - Downstream Analysis Map .........'.15 -1- lnsight ãngineering Co. - Storniwater $ìle Plan 1?^t2U2A17 Attachment 5 Acronyms and Abbreviations BLA BMP DOE EDDS ESC IECO MR SCDM SWPPP SV/MMWW TESC WWHM Boundary Line Adjustment Best Management Practices Department of Ecology Engineering Design and Development Standards Erosion and Sediment Conilol Insight Engineering Company Minimum Requirement SnohomishCounty Drainage Manual STormwater Pollution Prevention Plan Stormwater Managemenf Manual ftrr Western Washington Temporary Erosion and Sediment Control W'estern Washington Hydrology Model lneíght f;ngineering to. - $tarmwatsr Siie Plæn 12t2At2ü17 -2- Attachment 5 1.0 Executive Summary The proposed project Howell ll/ay Edmonds is locatecl at 318, Howell Way, Edmonds, Washington. More generally, the site is located in Section 26, Township 27 North, and Range 3 East of the Willamette Meridian in Snohomish Courty, Washington. Please refer to the Vicinity Map attached later in the section. This project is subject to the City of Edmond' s 2017 requirements and the requirements defined in I)OE's 2014 SWMMWW' The site area is 0.17 Acres. The site is cun'ently developed with an existing house, asphalt driveway ancl walkway from Howell Way. The remainder of the site exists as residential la¡dscaping. The site contains one drainage basin that slopes to the nodheast. Please refer to the downstream analysis map for more cletails. There are no critical areas located on the site. Per NRCS survey of Snohomish County, the project site contains Everett soils that have a hydrologic classification of Type "4". Please refer to the soils map and descdptions attached later in this report for more details. The project site is zoned as RM 2.4. The proposal is to construct a duplex lvith associated utilities. The access to the homes will be plovided fi'om alley to the west olthe property to Howell Way. The proposal also includes frontage improvements along Howell Way as per the City of Eclmonds Requirelnents. Per Figure 1.1, (Minirnum Requirements (MR's) for New Development) from Volurne I of the SWMMWW, Minimum requirements #1 though 9 shall apply for this project. See attachrnent C far Minimum Requirements Summaty included later in this reporl. Flow control requirements will be met by a Stormtank that provides infiltration at the base of the system. It will be located within the open area. Storm-tank modules of 36-in will be stacked ou top of storm tank modules of 36-in to make up to a depth of 6-ft. The total provided storage volume by the Stormtank is 1,257 CF. An infiltration rate of L4 in/hr per geotecturical recotnmendation was used within the hydraulic analysis. A geotechnical report is included in the appendix of this report. See Section 5 for more details. The onsite Stormwater managemeût requirement will be --3- lnsight Ëngineering Co. - $tormwater Site Pian 12t2U2.t17 Attachment 5 met by the Stormtarik system that will provide full infiltration. The imperviotts areas and the pervious areas w-ill be connected to the Stonntank system. The over'flow from the system will be connected to the existing drainage system along Howell Way. The proposed Stormtank system will store and infiltrate nuroff that is currently flowing in an unrestrained manner. No runoff is anticipated to leave the site. Therefore, the downstream public channel should not experience any futr-re flooding problems. Flow control requirements are exempt per section 2.5.7 of the SWMMWW because the Frontage Basin's effective impervious area is 986 SF which is less than the threshold of 10,000 SF, the prr:ject will not conveft 3Z acres of native vegetation to lawn, and the 10O-year flow frequency increase is 0.02 cfs which is less than the threshold of 0,1 cfs. The project is exempt for water quality because the new pollution genelating impervious surface is 2"493 SF which is less than the thleshold of 5,000 SF. The frontage basin is exempt for water quality because the new pollution genelating impervious surface is 564 SF which is less than the threshold of 5,000 SF. Per section 2.5.5 Minimum Requirenent #5: On-site Stonlwater Management, the following roof BI\4P's must be considered in the following order: Full Dispersion or Full Infiltration, Rain Gardens, Downspout Dispersion Systems, and Perlbtated Stub-out Connections. Full dispersion was considered first but it was cleterminecl that this option would not be a feasible option because the proposed project wouid not be able to meet the flow path requirement or the requirement for letaining at least 65 percent of native vegetation. The next consideration was infiltration. The project will provide an on-site stormwater infiltration facility using Stormtank System that provides infiltration at the base of the system to provide full infiltration. Per section 2.5.5 Minimum Requirement #5: On-site Stofflwater Management, the following other hard surt'aces BMP's must be considered in the following order: Full Dispersion, Permeable pavement, Rain Gardens and Sireet Flow Dispersion. Full dispersion was considered fir.st but it was determined that this option would not be a feasible option because the proposed project would not be able to meet the flow path requirement. Permeable pavement and rain gardens ale not feasible because of the presence of high water table which preclude installation of on-site infîitrative f¿cilities. Sheet Flow Dispersion is not t'easible because the required flow -4- lnsìght ãngíneer"ing Co. - $iorrnv¡ater $ite Plan 1?_.t2t!2û17 Attachment 5 path could not be met. The runoff ûnm the driveway and the alley will be directed to a catch basin. This will be connected to the onsite infiltration system. The runoff from the frontage sidewalk and road will sheet fiow to the catch basin along Howell Way. BMP T5.13 Post- Construction Soil Quality and Depth is proposed for additional stormwater management for the site. 5 lnsight Hngineering Co. - Såormwater $ite Pian 12"t2Ai2*17 Attachment 5 -9-!"i{j{it}z!t,ilìì id $:ì l; ..1{ì;tr^ÁLr.ìi*ls - .* } fi LìlJ#st r; r$?i }il *l*ir ìù1hiaa.J*,ñ"ìitfl"ì{ìa¡Y)iiJ{(i't.tÍËç".iiap )rl+:?í!)=a-/i:þ..:ftiJ<íì't,.',..,' *... '..., ' }-:iJ li:ri-i.4tl(,+l:.)lrrl]Ìlt¿ùiî;:rìr1fÅrì(\)rr)iì¡:.tjItiIIij'ì)la,í¡'iìiII-' "1IIiilt:35¡J.(rt.{Yl1t Ã"J.INßA' { trWfi * l":llåu'Êulrãðil!guðlrlE!su¡Oûtu I'¡ ¿9Ê6-e0r-sz?'gge6-80â-ç¿?90¿86Y¡/t'ìì,ðreÀ38¿tï xog't'd$) ss¿ì t*ä $t¡flNã str6$sl{ tSitluolãurqs€Å! úspu0rrpHspuilurpã Áe¡¡ ¡e'no¡1ffis.r.ñ:lIvfs8l,i8lt 3.1\r{IrçBù-¿ I.#ftût'[ÁüûrÀgueld ð$$ .¡ê1?j!r!ilJo]si,Õ QFIzç80-¿ t:UI{YÑ ã'II{Attachment 5 1.1 Minimum Requirements SummarY MR : MinÍmum Requirement S\ryPPP : Stormwater Pollution Prevention Plan MR #l Stormwater Site Plan Narrative: The Storuwater Site Plan pt'eparation follows the City of Edmonds 2017 requirements and in accordance with DOE's 2014 SWMMWW. Refer to the executive slrmmary within Section 1.0. MR #2 SWPPP Narrative: A SWPPP has been included in the Appendix A under Section 6 MR #3 Water Pollution Source Control for New Development: No source control pollutants pertains to the proposed single farnily project, tirerefore no BMP's are required for the project. MR #4 Preservation of Natural Drainage Systems and Outfalls: The root driveway and the alley will be connected to the onsite infiltration system. The cverflow from the infiitration system will be connected to the existing drainage system aloug l{owell Way to continue its natural drainage path. MR #5 Onsite Stormwater Management: Per section 2.5.5 Minimum Requirement #5: On-site Stormwater Management, the following roof BMP's must be considerecl in the following order: Full Dispersion or Full hfiltration, Rain Gardens, Downspout Dispersion Systems, and Perforated Stub-out Connections. Full dispersion rvas considered first but it was determined that this option would not be a feasible option because the proposed project woulcl not be able to meet the flow path requirement or the requirement for retaining at least 65 percent of native vegetation. The next consideration was infiltration. The project will provide an on-site stormwater infiltration facility using Stormtank Systern that provides infiltration at the base of the system to provide full infiltration. Per section 2.5.5 Minimum Requirement #5: On-site Stormwater Management, the f'oliowing other hard surfaces BMP's must be consiclered in the following order: Fuli Dispersion, 7 lnsight ãngineering Co. - Stcrmwatsr Sita Piæn 12"t24t2*17 Attachment 5 Permeable pavement, Rain Gardens and Sheet Flow Dispersion. Full dispersion was considered first but it was determined that this option would not be a feasible option because tire proposed project woulcl not be able to meet the flow path requirement. Permeable pavement and rain garclens are not feasible because of the presence of high w-ater table which preclude installation of on-site infiltrative facilities. Sheet Flow Dispersion is not feasible because the required flow path could not be met. The lunoff tì'om the driveway and the alley will be directed to a catch basin. This will be connected to the onsite infiltration system. The runoff fi'om the frontage sidewalk and road will sheet flow to the catch basin along Howell Way. BMP T5.13 Post- Construction Soil Quality and Depth is proposed for additional stormwater manageÍìent for the site. MR #6 Runoff Treatment: The project is exempt for water quality because the new pollution generating impervious surface is 2,493 SF which is less than the threshold of 5,000 SF. The frontage basin is exempt for water quality because the new polltrtion generating impervious surfaoe is 564 SF which is less than the threshold of 5,000 SF. MR #7 Flow Control: Flow control requirements will be rnet by a Stormtank that provides infiltration at the base of the system. It will be located within the open area. Storm-tank modules of 36-in will be stacked on top of storm tank modules of 36-in to make up to a depth of 6-ft. The total provided storage volume by the Stormtank is 1"257 CF. An infiltration rate of 1.4 inlhr per geotechnical recommendation was used within the hydlaulic analysis. A geotechnical report is included in the appendix of this rcpofi. See Section 5 fbr more details. The onsite Stormwater management requirement will be met by the Stormtank systeru that will provide full infiltration. The impervious areas and the pervious areas will be corurected to the Stormtank system. The overflow fi'om the system will be connected to the existing drainage system along Howell Way. The proposed Stolmtank system will store and irifiltrate runoff that is cunently flowing in an unrestrained manner. No runoff is anticipated to leave the site. Therefore, the downstream public channel should not experience any futurc flooding problems. Flow control requirements are exempt per section 2.5.7 af the SWMMWV/ because the Frontage Basin's effective impervious area is 986 SF which is less than the threshold of 10,000 SF. the prcrject will not conveft 3A acres lnsight ãngineering Co. - $lormwater $ite Fian -8- i2l2Ðt?-a17 Attachment 5 of native vegetation to lawn, and the 1O0-year flow frequency increase is 0.02 cfs which is less than the tlreshold of 0.1 cfs. MR #8 Wetlands Protection¡ There are no wetlands contained within the site. MR #9 Operations and Maintenance: Refer to Appendix B for a complete Operations and Maintenance Manual. lnoight Hngineering Co. - Stormwaier $ite Plan 9 12/24t2Q17 Attachment 5 2,0 ExÌsting Conditions The proposed project Howell Way Edmonrls is located at 318, Howeli Way, Edmonds, V/ashington. More generally, the site is located in Section 26, Township 27 North, and Range 3 East of the Willamette Meridian in Snohomish County, Washington. The site area is 0.17 Acres. The site is currently developed with an existing house, asphalt driveway and walkwai' from Howell Way. The remainder of the site exists as residential landscaping. The site contains one drainage basin that slopes to the northeast. Please refer to the downstream analysis map for more details. There are no cl'itical areas located on the site. Per NRCS survey of Snohomish County, the project site contains Everett soils that have a hydrologic classification of Type "4". Please refer to the soils map and descriptions attached later in this report for more details. lnsight f;nginaering Co. - Stcrrnwatsr Siìie Plan - i0- 12/2üt2017 Attachment 5 FIGURE 2. SOIL MAP Ìt l¡ SOILS LEGEND 17- Everett verv gravellv sandv loam. 0 to I percent slopes SITE INSIG}IT ENÊINËÊNIÑG €O. P.O. Box 1478 Everett, WA 98206 42S3039363, 425303-9362 f. lnfo@insightengineering.net rEc Fisure2-SoilMap Howell Way Edmonds Edmonds, \Mashington SCALE: NONE DATE: l/8/18 JOB #:17-0852 BY: JDM FILE NAME: t7-0852 \docs\drainage report lnsight ãngineering Cr. - *tarmwater Sile Plan 12^t2-Ai2A17 - lt - Attachment 5 Snohomish County Area, Washington l7-Everett very gravelly sandy loam, O to 8 percent slopes Map Unit Setting . National map unit symbol: 2t67g o Ëlevation: 30 to 900 feet. Mean annual precipítatìon; 35 to 91 inches. Mean annual air temperature: 48 to 52 degrees F. Frost-free period: 180 to 24o days. Farmland classification.' Farmland of statewide importance Map Unit Composition . Everettand similar sols;80 percent " Minor components: 20 percent. Estimates are based on obsentatians, descriptions, and transects of the mapunit, Description of Everett Setting . Landfarm.' Eskers, kames, moraineso Landform position (two-dimensional): Summit, shoulderc Landform positian (three-dímensional): Crest, interfluvec Down-slope shape.' Convexo Acrass-slope shape: Convexn Parent material: Sandy and gravelly glacial outwash Typical profile q Oi - A tu 7 inches: slightly decomposed plant materialo A - 1 to 3 inches: very gravelly sandy loam. Bw - 3 to 24 inches: very gravelly sandy loam. CI - 24 to 35 inches: very gravelly loamy sand. C2 * 35 to 6A inches: extremely cobbly coarse sand Properties and qualities . Slope: 0 to B percent. Depth to restrictive feature: More than B0 inches. Natural drainage class: Somewhat excessively drained. Capacity of the most limiting layer to transmit water (Ksat): High (1.98 to 5.95 in/hr). Depth to water table: More than B0 inches. Frequency af flaoding: Nonec Frequency of ponding; None " Available water storage in profile: Low (about 3,2 inches) Interpretive groups o Land capability classification (irrigated).' None specified. Land capability classification (nonirrigated): 4s. Hydrologic Soil Group: A. Ather vegetative classificatíon; Droughty Soils (G002XN402WA), Droughty Soils (G002XF403WA), Droughty Soils (G002XS401WA). Hydric soil rating: No Minor Components Alderwood -t2- ln*ight Ëngíneering Cr:. - $torrnv¡at*r $it* Pl¿tt 12i2rll2()17 Attachment 5 . Percent of map unit: 1A percent. Landform; Ridges, hillst Landform positian (two-dimensional): Summit. Landfarm position (three-dimensional): Crest, talf. Dawn-slope shape.' Linear, convexo Across-slope shape: Convexe Hydric soil rating: No Indianola . Percent af map unit: LO percent. Landform,' Eskers, kames, terraces. Landfarm position (three'dimensional):Tread. Down-slope shape.' Linear. Across-slope shape: Lineart Hydric soil rating: No tnsight fingineering Co. - Stormwater $ite Plan 12t2t!2ü17 -13- Attachment 5 3.0 Offsite Analysis A site reconnaissance was performed by Jacob D. Mealey of Insight Engineering on May 23 70,2017 to verify the downstream flow paths and observe any drainage problems downstream of the site. The sky was clear and was overcast with a temperature of 78 clegrees. The site area is 0.17 Acres. The site is currently developed with an existing house, asphalt driveway and walkway fì'om Howell Way. The remainder of the site exists as residential landscaping. Tlie site contains one drainage basin that slopes to the noúheast. 3.1 Upstream Analysis Based on the site reconnaissance and the topographic survey ofthe site" the upsüeam flows appear to be minimal. Refer to the Downstream Analysis Map attached in the next page for more details. 3,2 Downstream Analysis 3.2.1 Downstream Analysis for the Existing Flow Refer to the Downstream Analysis Maps I attached to the next pages for a visual description of the downstream flow. The Existing Downstream Path The existing site drains to the northwest and the flow enters the existing drainage system along Howell Way. It continues west for about i90-ft and turns north. The flow travels nofth for about 130-ft and discharges into the Shellabarger Cleek. The creek flows east for about 650-ft and enters the drainage system to cross the Edmonds Way. The flow then passes through Edmonds marsh and reenters the drainage system to cross the rail road. It finally drains into the Pudget Sound Basin. This is where the clrainage analysis was completed. There did not appear to be any restrictions or er¡sional problerns downstream of the site. -14- lnsight Engineoring Co. - Siormwatei- Siie Plen 12t24!2417 Attachment 5 FIGURE 3. DOWI\STREAM ANALYSIS MAP \+ ê7,/. ú æ I ä ¡t.{-#*g ñ l6 I a aù al7t &ä ú?+!tã t&þr ¡s !2¡a.& tla a al, 3aâ Õ Existing Flow I-la lrtlú SITE¡ I rNstglrr ExctNtËRtHg c0. P.O. Box 1478 Everett, WA 98206 429303-9363, 425303-9362 f . I nf o@insightengi neerlng.net ffiffiffi Figure 3 - Downstream Analvsis Man Howell Way Edmonds Edmonds, Washington SCALE: NONE DATE: li8l18 l7-0852JOB #: BY: JDM FILE NAME: 17-Q852 /do c/Stormwater Site Plan lnsight Ëngineering Co. - Stormwater Site Plan - 15 - 1212*t2t17 Attachment 5 4.0 Developecl Conditions The proposed project Howell Wøy Edmonrls is located at 318, Howell Way, Edmoncls, Washington. More generally, the site is locatecl in Section 26, Township 27 North, and Range 3 East of the Wiliamette Meridian in Snohomish County,'Washington. Per NRCS suvey of Snohomish County, the project site contains Everett soils that have a hydrologic classification of Type "A". The project site is zoned as RM 2.4. The proposal is to construct a duplex with associated utilities. The access to the homes will be provided frorn alley to the west of the property to Howell Way. The proposal also includes fi'ontage improvements along Howell Way as per the City of Edmonds Requirements. Per Figure 1.1, (Minimum Requirements (MR's) for New Development) from Volume I of the SWMMWW, Minirnum requirements #1 tlu'ough 9 shall apply fol this project. See attachment C for Minimum Requirements Summary included later in this report. Flow control requirements will be met by a Storntank that provides infiltration at the base of the system. It will be located within the open area. Storm-tank modules of 36-in will be stacked on top of storm tank rnodules of 36-in to make up to a depth of 6-ft. The total provided storage volume by the Stornrtank is 1,257 CF. An infiltration rate of 1.4 in/fu'per geotechnical recommendation was used within the hydraulic analysis. A geotechnical reporf is included in the appendix of this report. See Section 5 for more details. The onsite Stormwater manâgement requirement will be met by the Stormtank system that will provide full infiltratíon. The impervious areas and the pervious areas will be connected to the Stormtank system. The overflow from the system will be connected to the existing drainage system along Howell Way. The proposed Stormtank system will store and infiltrate runoff that is curently flowing in an unrestrained männer. No runoff is anticipated to leave the site. Therefore, the downstream public channel should not experience any future flooding problems. Flow control requirements are exempt per section 2.5.7 of the SWMMWW because the Frontage Basin's effective impervious area is 986 SF which is less than the threshold of 10,000 SF, the project will not convert ''/o actes of native vegetation to lawn, and -16- l:rsiçht Fngineering Co. - $tormwater $ite Plan 12t2{il2}17 Attachment 5 the 100-year flow frequency increase is 0.02 cfs which is less than the tfueshold of 0. I cfs. The project is exempt for water quality because the new pollution generating impelious surface is 2,493 SF which is less than the threshoid of 5,000 SF. The fi'ontage basin is exempt for water quality because the new pollution generating imperuious surface is 564 SF which is less than the threshold of 5,000 SF. Per section 2.5.5 Minimum Requirement #5: On-site Stormwater Management, the following roof BMP's must be considered in the following order: Full Dispersion or Full Infiltration, Rain Galdens, Downspout Dispersion Systems, and Perforated Stub-out Colnections. Full dispersion was considered first but it was determined that this option would not be a feasible option because the proposed project would not be able to meet the flow path requirement or the requirement for retaining at least 65 percent of native vegetation. The next consideration was infrltration. The pro.iect will provide an on-site stormwater infiltration faciiity tusing Stormtank System that provides infiltration at the base of the system to provide full infiltration. Per section 2.5.5 Minimum Requirement #5: On-site Stormwater Management, the followitig other hard surfaces BMP's must be considered in the fbllowing order: Full Dispersion, Pen¡eabie pavement, Rain Gardens and Sheet Flow f)ispersion. Full dispersion was considered first but it was determined that this option would not be a feasible option because the proposed proìect would not be able to meet the flow path requirement. Permeable pavement and rain gardens are not feasible because o1'the presence of high water table which preclude installation of on-site infiltrative facilities, Sheet Flow Dispersion is not feasible because the required flow path could not be met. The runoff from the driveway and the alley will be directed to a catch basin. This will be connected to the onsite infiltration system. The runoff from the flontagc sidewalk and road will sheet flow to the catch basin along Howeil Way. BMP T5.13 Post- Construction Soil Quality and Depth is proposed for additional stormwater management for the site. -t7- insíght Ënginaerirrg to. - Sicrmwaîer liile ?lan 12!?-Al2{}17 Attachment 5 5.0 Site Hydraulic Conditions to Determine Flow Control Constraints Per NRCS sul.vey of Snohomish County, the project site contains Everett soils that have a hydrologic classification of Type "4". Study Area* = 0"2'l Acres *The study areø includes the onsite area and the alley ta the west o/'tlze site. 5.1 Existing Basin SummarY Existing Basin : 0.21Acres Tþe existing basins was modeled as second growth forest. Ref'er to the Existing Basin Maps and the following pages for more details. 5.2 Developed BasÍn Summary .21 Developed Basin Impervious: Roof Area* (Ousite) Road (Alley) (Ofßite) Total impervious *The roofarea includes the coveredpcuio. Pervious: Pervious Area (Pastue) :0.13 Acres (5,802 SF) : t.21- 0.13 :0.08 Acres : A.2l Acres :0.08 Acres (3,309 SF):0.04 Acres (2,018 SF) 4 Infiltration Volume Required: 1,257 CF Infiltration Volume Provided: 1,257 CT The Stormtank will be provided to the north of the property underneath the open area. lnsight ängineering to. - $tcrrnwaier Site Plan - t8- 12"t20zt17 Attachment 5 Refer to the Developed Basin Map and the following pages for more details Refer t<¡ the following pages fol the WWHM rcport. Insight ängíneering Co. - $ir:rmrvater $ile Plan 1?.tztf2*17 -19- Attachment 5 AITÊY P55 r -*--5< * .*T"*--ra- " ----- lc ?ai_x__* .i .? sä 'ë .a Ir* I Ii_ I I I\ rl¡*eg i'o'Nli É1 - ffihT- !cJÉbdFr È{ <A cê ß g ë qê ! FIXÞ Ç¿ih'f)¡,'zql F .HE E .ili fùNIJ Attachment 5 ì{ät--¡,1riui'", --*--*f4¡e r,iVJPSDpdfHOWELLWAYäþ3PSS _rR0Nr¡6Ê 8/qs/N(a.02 Ac)ÐV 9AS|N(0.21 AC)aúøin",,(g]./I"ffi'o'01020DEVE,LOPEN BA,gT¡V MAPAttachment 5 wwHlc2012 PROJECT REPORT Pro3ect Name; Howell l¡lay slormtank Site Name: Howefl- Way Edmonds Site Address: 318 Howell Way, Edmonds, WA 98020-4118 City : Ed.monds Report Dale: 72/20/20L1-^^- /1v¡(5Þ ¡(egu-fr¡ ruVeL !dÞL! Datâ Start : L901, /1"0/1 Data End : 2058/09/3A DOT Ðata Number: 03 Version Date: 2016/02/25vêrsion : 4.2.L2 Low FLor¿ Threshold for POC 1 : 50 Percent of the 2 Year High Flow Threshold for POC 1: 50 year PREDEVELOPED I,AND USE Name : Exisitng Blpass; No Ground!üater: No Pervious Larld Use A B, Forest, Flat Pervious Total Tmpervious La¡¡d üse fmpervious fotal Basin Total acrê acre 0 0 .21 .2t o.2L / E1ement Flows To Surface Interflow Groundwater MTIIGATÊD LANÐ USE Name : Developed Blpass: Nc lnsigiit Ëngineering Co. - Siormwãtsr $iTâ plãn 20 12/2u2t17 Attachment 5 GroundWater: No Pervious Land Use A B, Pasture, Flat Pervious lotal Iupervious T,and tlse ROADS FÏ,AT ROOF TOPS FLAT DRIVE}ÍÀYS FI,AT Impervious lotal- Basin Total ¿¡'cre âcre 08 0.08 0. 13 4.2\ n 0 04 ^o 01 Elemenb Flows To: Surface Gravel Trench Bed 1 Inberflow Gravel- T'rench Bed 1 Groundwater Name : Gravel Trench Bed 1 Botton Length: 48.00 ft. ./ Bottom ÎIidth: 4.50 ft Trench boltom sloPe 1: 0 To 1 Trench Left side sJ-ope 0: 0 To 1 l"laterial- thickness of first ].ayer: 6 Pour Space of material for fírst layer: 0.91 Material thickness of second 3-ayer: 0 Pour Space of material for second layer: 0 l{aterial thickness of third layer: 0 Iìour Space of materíal for third layer: 0 Infiltration On /Infiltratíon rate: i.4 ( Infilt¡ation safety factor: 1 fotal Volu¡ne Infiltrated (ac*ft.): 49.291 fotal Volume Through Ríser (ac-ft' ) : 0 Total Volume Through Facilíty (ac-ft.): 49.29I Pêrcent Inf,iltrated: 100 fotaL Precip Apptied to Faci-líty: 0 Total Evap From Facility: 0 Ðischargie Structure Riser Height: 0 ft. Riser Diameter: 0 in, E]-ement Fl<¡ws To Outlet 1 Outlet 2 lnsight Ëngineering Co. - $tormr¡¡åter $ite plan 12i2Al?_{}17 AI Attachment 5 Gravel lrench Bed Hydraulic Table stage (feet) Ìlreâ (a.q . ) vo1üme (ac-f,t . ) Digcharge (ëfp) .Tqfil¿ (cfs) 0.0000 0.005 0.000 0. 000 0.000 0. 0667 0. 005 0.000 0. 000 0. 007 0. 1333 0.005 0.000 0. 000 0.00? 0. 2000 0.005 0.001 0. 000 0.007 0 .2661 0.005 0.001 0. 000 0.007 0. 3333 0.00s 0. 001 0. 000 0. 00? 0. 4000 0. 005 0. 001 0. 000 0. 007 o .466"t 0. 005 0. 002 0.000 0. 007 0. 5333 0.00s 0. 002 0.000 Û. 007 0.6000 û.005 0.002 0.000 0.007 0 .666'/ C . 005 0. 003 0. 000 0. 007 0 .7333 C.005 0. 003 0.0c0 0.007 0.8000 0.005 0. 003 0. 000 0. 007 0.8667 0.005 0.004 0.000 c.007 0. 9333 0. 00s 0. 004 0. 000 0. CIO? t" . rJ000 0.005 0. 004 0. 000 0. 00? 1 .066? 0.005 0. 005 0.000 0. Û07 1.1333 0.005 0.005 0.000 0.007 1.2000 0.005 0.005 0.000 0.007 L.266't 0. 005 0. 006 0. 000 0.0011.3333 0.005 0.006 0.000 0.0û7 1.4000 0.005 0.006 0.000 0.007 7 - 466'7 0. 005 0. 007 0 . 000 0 . 007 1 . s333 0. 005 0. 00? 0. 000 0.007 1 . 6000 0. 005 0. 007 0 . 000 0. 00? r.666'.1 0 . 005 0. 008 0 . 000 0. 007 1. 7333 0. 005 0. 008 0. 000 0. CIO? 1 . 8000 0.005 0. 008 0.000 0. 007 7.866't 0.005 0.009 0.000 0.007 1 . 9333 CI. 005 0. 009 0. 000 0. 007 2 . 0000 0. 005 0. 009 0.000 0. 00i ?.066'Ì 0.005 0.c09 0.000 0.00? 2 . 1333 0.005 0. 010 0. 000 0. 0072.2000 0.005 0.010 0.000 0.007 2.266'/ 0.005 0.010 c.000 0.007 2 . 3333 0. 005 0. 011 0. 000 0. 007 2.400a 0. 005 0. 01"1 0. 000 0. 007 2.4661 2.5333 2. 6000 2 .666"1 Z. I JJJ 2.8000 2.8661 2.9333 3. 0000 3. 0667 3.1333 3.2000 3 .2667 3. 3333 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0. 005 0. 005 0.005 0.005 0.005 0.0c5 0.000 0.000 0. 000 0. c00 0. 000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 û.000 0.000 0.011 0. 012 0.01.2 007 0CI? 00? 007 007 007 001 001 007 007 00? 00? 007 007 01 01 01 01 01 01" 01 01 01 01 U1 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. û. 0. 0. 0. 0. 0. 0. 0. 2 3 1.J 3 4 4 4 5 5 5 6 lrr*ight Engineering Co. - Str:rmwater $iie Pian 12t2{ii2ü17 Attachment 5 3.4000 0 0 0 0 0 0 0 0 0 U 0 {) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 01 01 01 01 01 01 01 01 Ul" 01 01 Q2 02 o2 02 02 r.4 3.5 3.6 J.O 3.7 J.t1 3.8 ?o 4.û Alt 4.1 d2 4.2 4.3 4.4 4.4 ¿.5 4.6 4.6 4.1 4.8 4.8 4.9 5.0 5.0 5.1 5.3ÈÀ 5.4 ET 5.6.-Ê E1 5,ð 5.8 5.9 6.0 66"7 333 000 661 333 000 661 333 UUU 661 333 000 661 JJJ 000 661 aaaJJJ ll00 661 333 000 66"7 333 000 661 )a) 000 661 1al 000 661 333 000 667 000 661 333 000 0.005 0. 005 0.005 0.005 0. 00s 0.005 0.005 0.005 0.005 U. UU) 0.005 0.005 0. 005 0. 005 0.005 0.005 0. 005 0. 005 0. 005 0.005 0.0CI5 0.005 0. 005 0. 005 0. 005 0. OCIs 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.00s 0. 005 0.005 0.005 0.005 0. 005 0. 005 . 021 n1) .022nt'ì .023 .024 .024 .024 .025ntq ô?q .426 .u1-ô .426 . CI26 . Q2'l .02'7 .021 .028 .028 .028 0. 000 0.000 0.000 0.000 0.000 0.000 0. 000 0.000 0.000 0. 000 0. 000 0.000 0. 000 0.000 0.000 0. 000 0.000 0.000 0.000 0.000 0.OCI0 0. 000 0.000 0.000 0.000 CI.000 0.000 0. 000 0. 000 0.000 c.000 0. 000 0. 000 0. 0û0 0.000 0.000 0.000 0.000 0. 00û 0.007 0.007 0.007 0.007 0.007 0.007 0.00? 0.00? 0.00? 0.007 0.007 0.00? 0. 007 0.007 0. c07 0.007 0.007 0.007 0.007 0.007 0.00? 0. c07 0.007 0.007 0. 007 0. 007 0. 007 0.007 0.007 0.007 0.007 c.007 0.00? c.00? 0.007 0.007 0.00? 0.007 0.007 016 k) 1 '1 1 B BI B 9 Ò 0 0 0 1 i ÀNAÍ,YSIS RSSUI,ÏS Stream Proteetion Ðuration Predevelopêd Landuse Totals for POC #1 Total Pervious Area.: 0.21 Total Inpervíous A¡ea:0 lnsight f;ngine*ring Cc. - $tormwater $i?a Pl*n -23 - 12!2812A17 Attachment 5 Mitigated Landuse Sotal-s for POC #1 Total Pervious Area:0, 08 fotal ftapervious Area:Û. 13 2 year 5 year 25 year 50 year 100 year Flow Freguency Return Periods for Predeveloped. POC #1 Return Period F]-ow (gfs) 0.000105 0.00013? 0.0001_53 0. 0001? 0.00018 0.000189 Flow Frequency Rêturn Periods for Mitigated. POC #1 Return Period FLow (cfs) 2 year 5 year 1O year 25 year 50 year 100 year 0 0 0 0 0 0 / Êtream Protection Ðuratíon ÀnnuaL Peaks for Predeveloped and Mítígated. POC #1 Year l'litiaated L9A2 1 903 1 904 1 905 190 6 1"901 . ÕnÕ 190 9 19L0 1911 L9L2 1 913 I9L4 1915 r9t6 791'7 1918 1919 7920 3"921 7922 7923 L924 L925 7926 r92'l :-928 t929 0.000 0. 000 0. 000 0.000 0. 000 0.000 0.000 0. 000 0. 000 0.000 0"000 0. 000 0.000 0. 000 0. 000 0. 000 0. 000 0. 000 0. 000 0.000 0. 000 0.000 0.000 0. 000 0. 000 0. 000 0. 000 0.000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0c 00 00 00 00 00 00 00 00 00 00 00 0.0CI0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.û 0.0 0.0 tnsight ñngineering Co. - Storrnv¡aler $ite Plan 24 12t20/2ti-i Attachment 5 1 930 1931 L932 1 933 r934 1 935 1 936 1 937 1 938 1S39 194 0 7941" 1942 194 3 194 4 194 5 L946 r947 t948 1949 1 950 1 951- 7952 l- 953 1954 1 955 1956 195 7 1958 195 9 r 960 L961_ r962 19 63 1964 1_965 L966 7961 1 968 1969 i 970 I9'¡7 1-912 791 3 197 4 i9"15 1.9"7 6I'77 197 B r97 9 i980 1981 7982 198 3 19B 4 0.000 0.000 0. 000 0.000 0.000 0. 000 0. 000 0.000 0. 000 0 - 0c10 0. 000 0.000 0.000 0. 000 0. 000 0.000 CI.000 0. 000 0. 000 0.000 0. 000 0.00CI 0.000 0.000 0.000 0. 000 0.000 0.000 0.000 0. 000 0. 000 0. 000 0.000 0. 000 0.000 0. c00 0.000 0.000 0. 000 0. 000 0. 000 0.000 0.000 0. 000 0. 000 0. 00CI 0. 000 0. 000 0.0Cr0 0. 000 0. 000 0.000 0.000 0.000 0.000 0. 00c 0.000 0.000 0. c00 0.000 0.000 0.000 0.000 0. 000 0"000 0.000 0. 000 0. 000 0. 000 0.000 0. 00c 0. 000 0. 000 0. 000 0. 000 0. 000 0.0û0 0.000 0.000 0.000 0. 000 0.000 0.000 0. 000 0.000 0. CIo0 0. 000 0.000 CI. 000 0.000 0.000 0.000 0.000 0.000 0. 000 0.00CI 0.000 0. 000 0.000 0. 000 0-000 0.000 0.000 0. 000 0.000 0. 00û 0. 000 0.0c0 0. 000 0. 000 lnsight f;ngineering Co. - $formweteir Site Piari 1?^t2*t2t17 Attachment 5 1 985 i986 r98'7 198I 198 9 19 90 i991 r992 1993 L994 1 995 r-996 l.99't 19 98 1 999 20 00 2001 2Q02 2 003 2CI04 2005 2At6 204'7 2008 2AA9 2 010 2OIL 20L2 2 013 2014 2 015 20r6 20L't 2 018 20t9 2020 2A2r 2022 2023 2024 2025 2A26 202-/ 2028 2029 2 030 2031,)ô?, 2033 2034 2035 2436 2t3'7 2C38 2439 0.000 0. û00 0.000 0. 000 0. 000 0.000 0.000 0.000 0. 000 0.000 0.000 0.000 0.000 0. 000 0.000 0. 000 0.000 0. 000 0.000 0. 000 0. 000 0. 000 0. 000 0.000 0. 000 0. 000 0. 000 0.000 0.000 c.000 0.000 0. 000 û.000 0. CIo0 0. 000 c .000 0. 000 0.000 0. 000 0. 000 0. 000 0.000 0. 000 0.000 0. 000 0. 000 0.000 0.000 0. 000 0.000 0.000 0. 000 0.000 0.000 0. 000 0.0û0 0. 000 0. 000 0.000 0. 000 0.000 0.000 0.000 0.000 0.0(i0 0.000 0.000 0.000 0. 000 0,000 0.000 0.000 0.000 0. 000 0.00c) 0.000 0.000 0.000 0. 000 0.000 0.000 0.00c 0. û00 0.000 0.000 0.000 0.000 0. 000 0. 000 0.000 0.000 0.000 0. 000 0. 000 0.000 0. 000 û. 000 0.000 0. 000 0. 000 0. 000 0. 000 0.000 0.00c 0. 000 0. 00û 0. 00c 0.000 0.000 0. 000 lnsight Ëngineering Co. - Stormweter Site Plan -26 - 12t2U2.A1i Attachment 5 204Q 2A4r 2442 2043 2044 2045 2046 204"7 2048 2050 205L 2052 2053 2054 2055 2CI56 2051 2058 0.000 0.000 û. 000 0. 000 0.000 0. 000 0.000 0. 000 0. 000 0.000 0.0CI0 0. 000 0. 000 0. 000 0. 000 0.000 0. 000 0.000 0.000 0 .000 0.000 0.000 0.000 0. 000 0.000 0.00c 0.00c 0. 000 0. 000 0.000 0. 000 0.000 0.000 0.000 0. 000 0. 000 POC *1 Stream Protection Duration Ranked Annual Peaks for Predeveloped and låitigated Rank Predeveloped Mitigated 0. CI002 0. 0000 0. 0002 0. 0000 0. CI002 0. 0000 0. 0002 û.0000 0.0002 0.0000 0. 0002 0. 0000 0. 0002 0.000{) 0. 0002 0.0000 0.0002 0.0000 0. c002 0. 00000.0002 0.0000 0. 0002 0. 00000.0002 0.0000 0.0002 0.0000 0. 0002 0. 00000.0002 0.0000 0. 0002 0.000c 0. 0002 0 .00000.0002 0.0000 0.0002 0.0000 0. 0002 0 .00000.0001 0.0000 0. 000L 0. 0000 0. 000r. 0. 00000.000L 0.00000.0001- 0.00000.000r- 0. 000û0.0001 0.00000.0001 0.0000 0. 0001 0. 0000CI.0001 0.0000 1 ¿ J ! 5 6 1I 9 t0 11 TI l-3 L4 15 16 17 1B 1.9 ¿.v ¿I,, 23 2A 25 ¿o 2t 2B 29 30 31 - ¿/ - i2i2t/2u"rlnsight f;ngineering Co. - $tormwaier $ite Plan Attachment 5 32 33 34 atr 36 31 3B 39 40 Á1 A1 43 44 45 46 4'7 4B 49 50 (1 52 53 54qq 56 57 5B 59 60 6L b¿. 63 64 65 66 61 68 69-t0 11. 1' '13 74 ;5'r6 '71 '78 19 BO BL B2 ÕJ B4 85 B6 0.0001 0. 0001 0.0001 0.0001 0.0001 0.0001 0. 0001_ 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001- 0. 0001 0.0001 0. 0001 0. 0001 0. 0001- 0. 0001 0.0001 0.0001 0. 0001 0.0001 0.0001 0.0001. 0.0001 0.0001 c. 00c1. 0.0001 0.0001 0. 0001 0. 0001 0. 000r- 0.0001 0.0001 c.0001 0.0001 0.000i- 0.0001 0. 0001 0. 0001 0. 0001 0. 0001 0.0001 0.0001 0. 0001 0. CIO01- 0. 0001 0. 000r- 0. 0001 0. 0c01 0. 0001 0.00CI1 0. 0001 0.0000 0 . 0000 û. 0000 0. 0000 0,0000 0. 0000 0. 0000 0. 0000 0.0000 0.0000 0.0000 0.0000 0. 0000 0.0000 0.0000 0.0000 0. 0000 0. 0000 0. 0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 c.0000 0.0000 0.0000 0. 0000 0.0000 0. 0000 0. 0000 0. 0000 0.0000 0.0000 0. 0000 0. 0000 0.0000 0. 0000 0. 0000 0. 0000 û.0000 0. 0000 0. 0000 0.0000 0.0000 0. 0000 0. 0000 0. 0000 0.0000 0.0000 lnsight fngineering Cc. - $larrnu¡at*r Sìie Fì*n -28 - 1220i2017 Attachment 5 B1 88 B9 90 97 92 93 o, q5 96 91 98 99 100 101 142 103 104 105 106 107 108 109 110 111 iL2 113 Ll4 115 1"76 177 1_ 18 119 120 ï2L L22 1"23 12.4 !¿J 126 1,2'7 128 1"29 L30 131 t32 133 134 135 136 1 5l 138 139 140 14L 0. 0001 0.0001 0. 0001 0. 0001 0. 000r. 0.0001 0. c001 c.0001 0. 0001 0. 0001 0.0001 0.0001 0. 0001 0. 0001_ 0.0001 0.0001 0.0001" 0.0001 0.0001 0.0001" 0.0001 0. 0001 0.000i 0. 0001 0.0001 0.0001 0. 0001 0 . 0001" 0. 0001 0.0001 0.0c01 0.0001. 0.0001 0.000r. 0. 0001 0.0001 0.0001_ 0.0001 0.0001 0.0001- 0.0001 0.0001 0.0001 0.0001 0. 0001 0. 000r. 0.000i 0. 00CIr- 0.0001 0. 0001 0. û001 0.0001 0.0001 0. 0001 0. 0001 0. 0000 0. 00c0 0.0000 0. 0000 0. 0000 0.0000 0. 0000 0. 0000 0.0000 0. 0000 0.0000 0.0000 0. 0000 0.0000 0.0000 0.0000 0. 0000 0.0000 0.0000 0.000c 0.0000 0.0000 0. 0000 0. 0000 0. 0000 0. CI000 c.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0. 000C| 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0. 0000 0. 0000 0.0000 0.0000 0. 0ûû0 0.00CI0 0.0000 0.0000 0. 0000 0. 0000 0.0000 0.0000 0. 0000 0. 0000 0.0000 ln*ight *.ngute*rinç Cr:. - $tormwatei Site plan -29 - 12t2*t?-û17 Attachment 5 L42 1{3 t-44 145 r46 141 148 1àq 150 151 1C1 'JL1i? 154 155 156 151 0.0001 0.000L 0.0001 0. 00CI1 0.0001 0.0001 0.0001 0. 0001 0.û001 0.0000 0 . 0000 0.0000 0.0000 0.0000 0. 0000 0. 0000 0.0000 0. 0000 0.0000 0. 0000 0. 0000 0.0000 0. 0000 0.0000 0. 0000 0.0000 0.0000 0. 0000 0.0000 0.0000 0. 0000 0. CI000 Stream Protection Ðuratiorì POC #1fhe Facility PÀSÊEÐ The Facíl-ity PÀSSED 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.000r- 0.0001 0.0001 0.0001 0 _ 0001 0.0001_ 0.000r- 0.000r. 0.0001 0.0001 0.0001 0.0001 0. 0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.00ût- 0.0001 0.0001 l'low (cfs)Predev 4620 4463 4L99 401 2 3952 3835 3583 3440 334 5 31 18 2992 291-9 2826 ¿ot I 2604 2530 2387 23AA 2248 2L66 2028 r_980 1888 L't 62 77 0L L644 1563 142:. 1_349 131- 1 Mit Percêntage Pass/l'aíl0 0 Pass0 0 Pass0 0 Pass0 0 Pass0 0 Pass 0 0 Pass0 0 Pass0 0 Pass0 0 Pâss 0 0 Pass0 0 Pass0 0 Pass0 0 Pass0 0 Pass0 0 Pass0 0 Pass0 0 Pa,ss0 0 Pass0 0 Fass U U PASS0 0 Pass0 0 Pass0 0 Pass 0 0 Pass0 0 Pass0 0 Pass0 0 Pass0 0 Pass 0 t Pass0 0 Pass 0.0001 0. 0001 lnsight Ingineering Cc. - $tormwaler Sìte Flan -30- 12t2u2t1'í Attachment 5 0. 0001 0. 0001 0.0001 0.000L 0.0001 0. 0001 0.0001 0.0001 0.0001 0.0001 0. 0001 0. 0001 0. 0001 0.000:r 0.0001 0.0001 0. 0001 0. 0001 0.000r. 0.0001 0.0001 0.0001 0.0001 0 . 0001" 0.0001 0.0001 0. 0001 0.0001 0.0001 0.0001 0.0001 0. 0001 0. 0001_ 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001. 0.0001 0.0001 0. 00ûr- 0.0001 0.0001 0.0002 0. 0002 0. 0002 CI. 0002 0. 0002 0. 0002 0.0002 0. 0CI02 0.0002 1209 L175 113 6 1_065 102 3 980 941 BB3 859 OJJ 19"1 168 154 "7 32 684 634 674 570q'r? 501 489 457 438 418 394 382 .JO¿ 344 322 310 305 290 27r 258 aAa l?Ê 229 214 L89 LB1 186 L11 i 61 15¿ 133 L23 119ir6 LU¿ 94 B1 17 59 56 52 0 c 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Pass Pass Pass Pass Pass rdÞÞ Pass Pass Pass Pass f):cc Pâss Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pâss Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pess Pass Pass Pass Pass Pass Pass Pass Þacq Pass Pass Pass Pass Pass Pass Pass Pass Pass lnsighi Ër':gineering Co. - $tor*rwetei Site Pl*n 12"t202ô17 -31- Attachment 5 0.0002 0.0002 û.00c2 0.0002 0. 0002 0. 0002 0. 0002 c.0002 c.0002 ^ .lnnt 0.0c02 0.0002 0.0002 0. 0002 û. 0002 Pass Pass Pass Pass Þrcc Pass Pass Pass Pass Pass Pas s Pass Pass Pðs s 4B 32 30t) 4 ¿I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 water Quality BMP f'l"ow and volut0ê f,or FoC #1 On-Line facil-ity wolume: 0 acte-f,êêt On-line facil-iùy targe! f:.owí 0 cfs, Àdjusted for 1"5 min: 0 cfs. off-linê facj-lity target f].ôw: C cfs' Àdjusted for 15 nL:j.n: 0 cfs. f.lD Report LfD TechniquePercent Water Quality Used for PercenL Treatment? tùaLer Quality Totêl Volumn VoJ-urnn Through Facility L n Il..l.t raL ron VoIumn (ac-ft. ) Cumufative Volunn Infiltrati-on CÕfûr'.ent Needs '.¡ol-urnn Trîeatnent Jnfi.ltrated Treated Gravei rrench Bed 1 poc - - ì#Liac-ft) ---- credii N 99 .92Total Voìurne lnfittrðted 44.89 0.00 0.00 99,92 0.00 0t No Treat. Credii Comptiance with LID sta¡darcì B Duration Ana.lyeis Result = Passed Perlnd and Inplnd Changes No changes have been made This progran and âccômpanying documentation ère provided 'as-is' htithout wårranty of any kind. Tbe entire risk regarding the performance and resu]-ts of this program is assuned by End User. Cleer Creek Solutions Inc. ând the governmental licensee or sublicensees disc.lain all warranties, elthetî expressed or implied, incJ.uding but not limj.ted lo implied vràrranties of program and accompanying documentatj-ûn. ln no event shall Clear Creek Solutions Inc. be liabl"e for any damages whatsoever (including Írithorìt Limitatio¡r to daaages fôr loss oi busines6 profits, lÒss of business informaiion, busilless interruptiÒn¿ and the 1íke) arising out of the use of' or inability to use this progrân even if Clear Creek So.lulj.ons Inc. or their authorí¿ed representatíves have been advised of the possibí.lity of such damages. Softhtare Copyright O by : Cteâr Creek So1utíons, Inc. 2005-2017; ÀLl Rights Reserved. lnsight Hngineering Cc¡. - Stormwater $iTe Plan 32 12l2rll2C17 Attachment 5 5.3 Frontage Basin Summary Frontage Basin 5.3.1 Existing Frontage Basin Summary = 0.02 Acres Existing Frontage Basin :0.02 Acres The existing basins was modeled as seconcl growth forest. Refer to the Existing Basin Maps and the following pages for more details. 5.3.2 Developed Frontage Basin Summary Developecl Frontage Basin Impervious: Road :0.0i Acres (564 SF) Total Impervious :4.02 Acres (986 SF) Pervious: Pervious Area : 0 100-yr Peak Flow Inclease : 0.02 cfs - 0 cfs : 0.02 cfs < 0.I cfs Thereforc, the frontage basin is exempt fi'om flow control and it will be bypassecl - 0.02 Acres lnsíght f,ngineering Co. - $tçrmwater Site Êian JJ 12t2út?-C1'T Attachment 5 wwHM2012 PRO.TECT REPORT Project Name: Howell Bypass Sitê Narnê: HowelJ Way Edmonds Site Address¡ 318 Howell tr'üay, Edmonds' City : Edmonds Report Ðate: 12l5/2A1'7 MGS Regoín : Puget East Ðâta Start : t90I/I0/7 Data End : 2058/Q9/30 DOT Data Number: 03 Version Ðate: 2CI1,6/02/25 Version : 4.2.L2 tlA 98020-4 118 Low Flow Threshold for POC L : 50 Percent of the 2 Year High Flow Threshold for POC 1: 50 year PREÐEVELOPED I.AND I'Sg Name : Exisitng Bypass Blpass: ll<r 4roundWater: No Pervious Land Use A B, Forest, Flat Pervi-ous Total Irrpervious Land Use Impervious Total Basin Tota]. a.crê \r.02 0. 02 acre 0 0.02 Element Flows lo: Surface Interflor.c Groundwater MTTIGATED T,AND I'SE Name : Developed Bypass Blpass: No lnsight Ëngineering Cc. - $törmwatei $ite Pian -34- 12t7ttl2A17 Attachment 5 GroundWater: No Pervious Land Use Pe¡vi.ous [ota1 Impervigus Land Use ROÀÐS rr.,AT STÐE}TAÍ,KS FI.AT Tmpervious fotal Basín Total- acre acrê 0.01 0. 01 0.02 0. 02 0 ^l Element, Flows fo Surface Interflow Groundwater .Ar{ÀtYsrs Fgsuï,îs Stream Protection Ðuration PredeveJ-oped Landusê Totals for POC #1 Total Pervious .Area: 0 . 02 Total Impervious Area:0 Ifitigated T,anduse Totals for POC #1TotaL Pervious J\rea:0 TotaL lmpervious Arear 0, 02 Flow Frequency Return Periods for Predeweloped Return Period Flow(cfs)I year 5 yaar 10 year 25 year 50 year 100 year 2 year 5 year 10 year 0.00601s 0 . 008l"2s 0.009699 POc #1 0. 0. 0. 0. 0. 0. 0000 1 0 0 0013 00 0 015 000016 00 0 017 000018 Flow Freguency Returr¡ Períods for Mit,igated. POC #1Return Period Flow(cfs) insight f;ngineering f,o. - $tcrmy¡ater Sìle Pian 35 12t2til2a17 Attachment 5 25 year 50 year 100 year 0. 011897 0. c13693 0.015633 lhe deveJ.opmen! has ar¡ increasê in flow durations f,tom !/2 Predevelo¡rêd 2 year f].ô}' to ttre 2 year flow ôtr môrê than a 10t inc¡ease from the 2 yeat to the 50 !"èa¡ f]Òi.r.the dewelopment has a$ j-r¡crease in fLô?r duratíons for mofe than 50t of the flows for thê range of thedu¡ation âr¡aLysis, Watêr Quâlity 8MF tr'losr ärrd VoLume f,or POC #1On-line facj.Lity volumê: 0 acre-feet On-l"ine faci].ity target fLow: 0 cfe. Adjusted for 15 ûin: 0 cfs.Off-line faciJ-ity target fl"Õw: 0 cfs.Adjusted for 15 nÍn: 0 cfs. Í.ïD Rêport f,lt, TechniquePercent Wacer Quality t:cìurnn I nfiltrated Used for Tôtèl volu¡nnPercenÈ Conment?reatment? Needs Water Quality lreatment Trêated (ac-ft) Vôlumn Throrìgh Fåcility íac*fl l In fil-tration Vô.1"urftIl (ac-ft. ) cumulative VoIunn lnfil tra tlon Credit lnsíght Fngineering Ca. - Sfcrmwatsf Site pl*l1 JO 12/2.ti2*17 Attachment 5 5.4 Water Quality The project is exenrpt for water quality because the new pollution genemting impervious surface is 2,493 SF which is less than the threshold of 5,000 SF. The frontage basin is exempt for water quality because the new pollution generating impervious surface is 564 SF which is less than the threshold of 5,000 SF. lnsíçht Engineering Os. - Stormlvater Site Plan - 3t - 12í2012t17 Attachment 5 A. STORMWATER POLLUTION PREVENTION PLAN This Stormwater Pollution Prevention Plan (SWPPP) has been prepared as paft of tlie construction stormwater permil rcquirements for the project Howell lvny Edmoruls in Edmonds, Washington.. Itis located in Section 26, Township 27 Norlh, and Range 3 East of the Willamette Meri<iian in snohomish County, Washington. The site area is 0.17 Acres. The site is cu¡ently developed with an existing house, asphalt driveway ancl walkway from Howell Way. The rcmainder of the site exists as residential landscaping. The site contains one drainage basin that slopes to the nofiheast. Please refer to the downstrearn analysis üìap for more details. There are no clitical areas located on the site. Pe¡ NRCS suryey of Snoho¡nish County, the project site contains Everett soils that have a hydrologic classification of Type "4". please refèr to the soils map and clescriptions attached later in this report fbr more details.Flow cont¡ol requirements will be met by a Stormtank that provides infilration at the base of t¡e system. It will be located within the open area' Storm-tank modules of 36-in will be stacked on top of storm tank modules of 36-in to make up to a depth of 6-ft. The total provided storage volume by the Stonntank is 1,257 CF' An infiltration rate of 1.4 inlhl per geotechnical recommendation was used within the hydraulic analysis. A geotechnical report is included in the appendix of this repoft. See Section 5 for more details. The onsite Stormwater management requirement w'ill be met by the Stormtank system that will provide full infîltration. The impervious areas and the pervious areas will be connected to the Stormtank system. The overflow from the systern will be comected to the existing drainage system along Howell Way. The proposed Stormtank system will store and infiltrate ruuoffthat is currently flowing in an unrestrained manner. No runoff is anticipated to leave the site' Therefore, the downstream public channel should not experience any future flooding problems. Flow control requirements are exempt per section 2.5.7 of the SWMMWV/ because the Frontage Basin's effective impervious area is 986 SF which is less than the thrcshold of 10,000 SF, the project will not convert 3/q aqes of native vegetation to lawn, and the 1gg-year flow frequency incrcase is 0-02 cfs which is less than the threshold of 0.1 cfs. The project is exempt for water quality because the new pollution generating impervious surface is 2,493 SF which is less than the threshold of 5,000 SF. The frontage basin is exempt for water quality lnsight Engirreering Co. - $îc¡rmw*ter Site ?lan -39 - 1?-t20/2ü17 Attachment 5 because the new pollution generating impervious surfl¿ce is 564 SF which is less than the threshold of 5,û00 SF. The purpose of this SWPPP is to clesøibe the proposed consfruction activities and all tenrporary and permanent erosion and sediment control (TESC) measures, pollutiori preventiorr measures, inspectiorlmonitoring activities, and recordkeeping that will be implemented duling the proposed constn¡ction project. The objectives of the SWPPP are ro: l. Implement Best Management Practices (BMPs) to prevent erosion ancl sedimentation, and to identify, reduce, eliminate or prevent stormwater contamination and water pollution flom construction activity. Prevent violations of surface water quality, ground water quality, or sediment management stanclarcls. Prevent, cluring the construction phase, adverse water quality impacts including impacts on beneficial uses of the receiving water by controlling peak flow rates and volumes of stormwaïer runoff at the Permittee's outfalls and downstrearn of the outfälls. This SWPPP was prepared using the Ecology SWPPP Tenrplate. This SWPPP was prepared based on the requircments set foth in the Construction Stormwater General Perlnit and in the Stormwater Management Manual for Westem V/ashington (SV/MMWW 2005). 2 3 lnsiEht ãngineering Co. - $icrmw*ter $ite Plan ..40 - 12i2t!2t17 Attachment 5 The 13 BMP Elements Element #l - Mark Cleari4s.L-Ímits To protect adjacent properties and to reduce the area ofsoil exposed to construction, the lirnits of construction will be clearly marked before land-clisturbing activities begin. Element #2 - Establish Ço4struction Access Construction access or activities occuring on unpavecl areas shall be minimized, yet --.L^-^ -^i-¿^ ^L^lt I^^ ^¿^L"'l:*^l t^ --^1,-i-^-l--^ ¿l- - ¿ -- -f -!,- - f r:wlrçr.ç rrçççb¡raty. au\,çùù purrllù slralr uç staull.r¿çu [u illr.llilill¿c lilc u¿1ÇKlllg ot sçullllcilt onto public roads, and wheel washing, street sweeping, and street cleaning shall be ernployed to prevent sediment 1Ìom entering state waters. fnstall the temporary construction entrance, according to the approved construction plans, prior to any clearing or grading activities. Maintain until the access road is paved. Eleme4f #3 * Control FIow Rates. In order to protect the properties and waterways downstream c¡f the project site, stormwater discharges irom the site will be controlled. In general, discharge rates of stormwater from the site will be controlled whele increases in irnpervious aì'ea or soil compaction during construction could lead to downstrearn erosion, or where necessary to meet local agency stonnwater discharge requirements. Element #4 * Install Sedinlent Controls Instail silt fencing, according to the approved plans, plior to any clearing or grading activities. Maintain until all construction activities are completed. install catch basin filters, according to the approvecl construction plans, as catch basins become operable. Maintain until all construction activities are completed. Slement #5 - Stabilize Soils Exposed and un-worked soils shall be stabilized with the application of effective BMPs to plevent erosion throughout the life ofthe proiect. Apply temporary hydro-seed to exposed and un-worked soils, according to the approved construction plans, as needed to prevert erosion during site grading. Apply permanent hydro- seed to areas at final grade as site grading is completed. Apply mulching to exposed and un-worked soils, according to the apprnved construction plans, as needed to prevent etosion during site grading. Maintain until site grading is completed and permanent hydro-seed is applied. Cover stockpiles with plastic sheeting, according to the approved construction plans, as needed to prevent erosion duling site grading. Maintain until stockpiles ale removed fi'om site. Element #6 - Protect Slones All cut and fill slopes will be designed, constructed, and protected in a manner than minimizes erosion. The following specific BMPs will be used to protect slopes fbl this project. Element #7 - Protecú Drain Inlets lnsight *"ngtneering Co. - $tormwaier $ite Plæir -41- 12tzt/2t17 Attachment 5 All storm drain inlets and culveds made operable during construction shall be protected to prevent unfiltered or untreated water from entering the drainage conveyance system. However, the first priority is to keep all access roacis clean of sediment and keep strcet wash water separate from entering stonn drains until treatment can be prnvided. Element f8: Stabilize Channels and Outlets Where site runoff is to be conveyed in channels, or dischargecl to a stream or sonre other natural drainage point, efforts will be taken to nrevent downstream elosion. Element #9 - Control Pollutants All pollutants, including waste materials and demolition debris, that occur onsite shall be handled and disposed of in a maruler that does not cause contamination of stormwater. Good housekeeping and preventative measures will be taken to ensure that the site will be kept clean, well organized. and free of debris. Elg.q"gnt #10 - Çontrol Dewatering Tlrere will be no dewatering expected as part of this proposal. If it occurs, Baker tanks will be used for dewatering. Elernent #Il - Maintai$ BMPs All temporary and permanent erosion and sediment control BMPs shall be maintained and repaired as needed to assure continued performance of their intended function. Maintenance ancl repair shall be conducted in accordance with each particular BMP's specifications. Visual monitoring of the BMPs will be conducted at least once every calendar week and within 24 hours of any rainfall event that causes a discharge fi'om the site. If the site becomes inactive, and is temporarily stabilized, the inspection frequency will be reduced to once every month. All temporåry erosion and sediment control BMPs shall be removed within 30 days after the final site stabilization is achieved or after the temporary BMPs are no ionger neecled. Trapped sediment shall be removed or stabilized on site. Disturbed soil lesulting û'om removal of BMPs or vegetation shall be permanently stabilized. fn*ight Ëngíneering Co. - $tormwater Sìte Pl¿n 42 12t2U2A17 Attachment 5 Element #12 - Manase tþe Proiect Erosion and sediment control BMPs for this project have been designed based on the following principles: Design the project to fit the existing topography, soils, ancl drainage patteüìs; Emphasize erosion control rather than sediment control; Minimize the extent and duration of the ârea exposed; Keep runoff velocities low; Retain sediment on site; Thoroughly monitor site and maintain all ESC tneasures and Schedule major eafthwork during the dry seâson. The SWPPP shall be modified as necessary to include additional or modified BMPs clesigned to coüect problems identified. Revisions to the SWPPP shall be completed within seven (7) clays following the inspection. Element #13 -Jrotect On-site Stormwater Manasement BMPs for Runoff from Roofs andOtþr Hard Surfaces On-site stolmwater tnanagenrent IIMPs r¡sed for runofifrom roofs and other hard surfàces include: ftill dispersion, roof downspout full inliltration or dispersion systents, perforated stubcut connections, rain gardens, bioretention systems, permeable pavemeil, sheetflow dispersion, and concentrated flow dispersion. The areâs on the site to be used fol these BMPs shall be protected fi'orn siltation and oompaction during construction by sequencing the construction in a fashion to install these BMPs at the latter part of the construction grading operations, by excluding equipment fiom the BMPS and the associated areas, and by using the erosion and sedimentation confi'ol BMPs listed below. Additional requirements for prctecting these BMPs during the construction process, testing functionality, and restoring functionality are needed at the final stage of the construction pfocess. Relevaqf BMPs BMP C102: Buffbr Zone BMP C103: High Visibility Fence BMP C200: Interceptor Dike and Swale BMP C201: Grass-lined Cirannels BMP C207: Check Dams BMP C208: Triangular Silt Dike BMP C23I: Brush Banier BMP C233: Siit Fence BMP C234: Vegetated Strip ìnsight ñngíneering f*. - $åorrnr¡¡atei $ile Plan i2t?.0t2*17 -43- Attachment 5 B. OPERATIONS AND MATNTENANCE MANUAL The facilities that require periodic maintenance for this proiect are as follows. o Stormtanko Catch basinso Catch basin Insertsc Conveyance Storm Pipes Refer to the following pages for facilities trrat require maintenance. lnsight Ëngineering Co. - $tsrmuvæter $ite plan -44- ,2t2A!2*17 Attachment 5 l#¿¡#¿¡ls þTainlenåncs ü¡"ridelines General: The Stormïank'" Stormwater Starage Module is a component in a sïormwater collectìcn system, providing storâge for the detention or infiltration nf runoff. Iilo two systerfis are th* same; with varying shapes, si¿es and configuratiens. Some in¿iude pre-treatment tc remcve sediment and/or rûntãffìinänts pr¡ûr t8 entering the storage arsa and scme do nfi. System$ without pre-treatm€ñt require greäter attûntiÕn to systeÍT1 functionality and mav require additional maintenance, ln arder ta sustain system functionality Erentwood offers the followirrg general maintena¡rce guiclelines Precautions: 1. Priör to & During Constructi*n - $iltation prevention of the stsrmwater system. a. Ctnforrn to ail local, state and federal regulations fsr sediment and erosion control during construction" b. lilställ sitÊ ernsicn and sediment BMF's {Best li{anagen:ent Practices} r*quired to prevënt siltation of the storrnwäter system. r. Tnspect and maìntain erosìnn and sediment BMP's during constructian. 3. Post Construction - Frior tn conrmissioning the $torrnïånk"" systern. a. Remcve and properly dispose of constn¡ction erosion and sedime nT 8fulP's per all local, state and federal regulations. Care shauld be taken during rcnroval of lhc *MP's as n*ì to allcw callected sediment sr debris into the strrrnwüter systen1. b. Flush the StormTank'" system to remove any sediment or construction debris imm*diately afïer the BMP's removal. Follow the nraintenance procedure outlined. lnrpectionsl Follow all local, sTale, ånd federal regulations regarding strrñwåtËr BMp inspection rÊquirements. Erentwond lndustries ma kss the lallowing recomn:endalions: L. Frequency a. During the first service year a visual inspecti*n should be completed during and after each nrajor rainfall event, in addition to semi-annually, to esTablish ã pattern of setiinrent and debris buildup. L5 snsmv'woon. RevisiÕn:61û Morgãntown Road, Reading. PA 196j"1 P:61^t-374-51ü9 F:6L0-736-1280 [mail: Stûrìrgiitie,ljàþrêñr&'ûñdirìdv5.trjËs.q-çrï9/17/11 1of I Attachment 5 i. tach ltormwater system is unique and multiple criteria c*n affect maintenance frequency $uch as: ä) Systen Design: pre-treatrnenl/no-pretreatment, inlet prctection, stand alnne device. b) 5ur{ace Area Collecting From: hardscape, gravel, sail, ci Adjacent Area; soil runoff, gravel, trash. i\ c^^^^,.^t al, ^^^^-, t-ll l^^..^- rr,;a&ÃÉ ^-l+l-i^Å^--u, Jcd)vllg, Llrallåç¡. ìGlr-rccvc), Y9¡ù[çr-5ort/Lrrlugl¡. b. Secnnd year plus; estãbl¡$h an annual inspection frequency based on the info¡maticn collecled cluring the first year. At a minimum an inspection should be p*rfcrm semi-annually. c. Seasonal change; regianal areas affectecl by seasonal change {spring, surnmerr fall, winter) may require additional inspecticns at the change of seascns in addition ta semi-annually, 2. lnspect: a. lnspectiûn ports. b. lnflow and autflaw points including the inlet/manhe¡le and pipes c. Discharge area. 3. ldentify and Report mðintånãnce required: a. Sediment and debris aecunrr¡lâtion, b. System backing up. c. Flow rate change. Maintenance Prsredures: l. Conform to all iocal, state and federal regulations. 2. Determine if maintenance is required. lf a pre-treatment device is installed, foilow manufaeturer recommendations. 3. Using a vãcuum pump truck evacu;te debris frçm the inflow and outflow points. 4. Flush the system with clean water forcing debris from the system. Take care to avaid extreme direct water prëssure when flushing the system. 5. Repeat steps 3 and 4 until no debris is evident. These maintenance guidelinå$ werÊ wrilten by Brentwood lndustries, lnc. with the express purpose cf providing helpful hints. These guidelines ârä nÕt ta b,e construed as the cnly Brentwood approved methods fsr StormTank'" system maintenance or the final authority in system mäintenånce. Check with the st*rmwatÊr systërn owner/project e ngineer far their corilract/specificaticn reqirirenents and ur recommendations. Csntact your local $tormïank'" distrihutor or Brentwood lndustries for additionel technical support if required. ffi anEmrwüon" fievisiôn:6l.t Morgantowr Road, Reading, PÅ 1963^1 P: 6Lû-374-51"û9 F: 610-736-1.280 Ernail: Stornrwatsrß}hÍsntl,r¡gÊrljin{}.$lije¡"Etçileh2/13 I of l Attachment 5 No.5-tatchBasins r*oiurze l* * l*tnoîTt"Èdttil?crrt EMPs - üeeeml¡ey 3A14 4-38 Maintenanee Component Conditions When Mainten*nce is Needed Results Expected When MaintenanÐe isperformed Trash or debris which i$ loçated immediatelv in front of the catch basin opening or isblockinq inle,ttinq cãÐâcitv ôf thê iJåsin hv more thãn 10%." No Trash or deþ¡is located immediately in front of e rlnh h¡cin ñr ñn ^r-+ô0Fenrng. Trash or debris (ìn The basin) that exceeds 6üpercent of the sr-rmp depth as measured fronlthe bottom of basin to invêrt ol the iowestpipê into or out of the basin, but irr no caseless than â min¡nlum of six inches clearançefrom the dehris surface tr thê inver't ùf thêÌowest pipe. iilo trash 0r dëbris ¡n the catch b*sin. Trash or debris in anv inlet or cutlet uineblocking more than 1i3 of ¡ts height. ' 'lnlel a¡rd oullet 0ioes free of trash or debris Trash &tebris Dead animals or vegetât¡on that couldgenerãïe ador$ thât could cause complaints ûr dangerûus gaaes (e.g., methane). ' No dead ânhnâls 0r vegetation present w¡th¡n the catch basin. Sediment $ediment (in the ba$in) that exceeds 60percent ofthe sunìp depth as measured fromthe bottom of basin to lnveri of the lowestpipe into ci out ofthe basin, but in no caseless than a minimr¡m of 6 ¡nches cleårancefrom the secliment surfaûe to fhe inverl ol thelowest pipe. No sedinient hì the câtchtr*sil Top slab hâ$ holes larger than 2 squareinches or cracks wider than 1/4 rnch {lntçnI i$ to näke sure no material is runnìnginto basin). Top slab is free of hslee and cracks. $tructure Damage to Fru¡xe and/or Top $lab Frarne not sitting flush on Top slab, i.e., separaticln cf more than 314 ínch of thc frsme from the top slab. Frafie not securelyåttâched Frame is si1{ing flush orr the r¡ser nngs ór top slab and firmly attachecl. Mâintenance person judges that structure isuns0und.Basin replaced or repairec{ to design standards. Fractures or Õracks in Basín Wallsl Bottom Grout fillet has separated or cracked widerthan 112 inch and longer than 1 foot at thejoint of any inleUoutlet pipe or any evidence ofsorl part¡cfe$ entering catöh basin throughcracks. Pipe is regrouted and$tcure 9t basin wall. Settlernenf Misalignment lf failure of basin has cËâted a sâfëtv funclion, or design prOhlen.Basin replacecl or repaired io design slandärds. Vegetation growing âcross and blocking rnorethan '10olo of the básin opening. No vegetatíon blocking open¡ng to basin. General Vegetatiün Vegetaiion growing in inlet/ouflet pÌËe ¡ointsthat ¡s more than six inches tall and leés than nix ínches apart. No vegetation ot rÖotgrowth present. Contaminaticn and Pollution $ee "Detention Ponds" (No. 1).No paliuiinn pre$ent. Yor¡ created this FÛF fionr an applicafian thai is not lice¡sed ta print to novaPDF p¡-¡nter {Ellp:iiwww-flgfgËgLçSm)Attachment 5 No.$*tatchtsasins Na.6 - üebrls þarrlers {e.9", Trash Racks} l,olwne {ì * llunofl' l'reeiffieftt 81.Íljs *.Ðec:ewÍ¡er 2014 4-3ç Mäintênance Gomponent Defeet Conditione lf9hen llllaintenanee is Heeded Results Expêetêd When Maintenanc¿ is perfonned tatch Basin Cover Cover Not in Place üover is m¡ss¡ng or only padially in place. Any open catch basin requires maintenance. CÊtch ba$¡n cover is I n¡Þina Mechanism t,lot Working äil¡ahaaì¡* ^^^^^+ h^ an¡^^d L., ^^-Nrçur rGr ¡rùr I f ç.| ¡r rwL ùç uPçr tçu !y vt tc ma¡ntenance per$on with proper tools Eoltsinlo frarne have less than 1/2 inch of thread. Àr--r---^:-,-,,--,rvruLilãil¡sn t ufjcils wrlf ì prnper tools. tover Difficult to ftemove One maintenance per$tn ænnûl remüve lidafter applying nornal lifting prs-qsure. {lntent ís keep cover from sealing off access to maintenance.) Cover can bre removed bv one nlaintenance person. Ladder Ladder Rungs Unsafe Ladder is ungafe due to miusing rungs, nût securely attached to bauin wall, misalignment, rugt, cracks. cr *harp edge*. Ladder meets desian standards and allaü¡s måi¡ltenanöe per'son saf* svÇcÞ)- Metâl ûrctes {lf Applicahle) Grate opening Unsafe Grate with openlng wider than 7¡'â inch trate opening meets desìgn standards. Trash and tebrìs Trash and debr¡s thât is blacking nore than 20o1o of grate surface inleiiing capacity. ü¡ate fiee Õf trâ$h änd debrìs. Damaged or Missing trate missing or brohen member(s) *f the Grate is ín place and meefs design standards. lllleintenanee Componenta DÊtuct Csndition \41?'¡en Mainùanance is Needed Results Expected When Mai ntenanee is Psrlormed General Trash and üebris Trash or debris that is plugging more than 20% of the openings in the barrier Barrier. cleared to design flow capâcrry. Metal Damaged/ Missing Bars. Bars are bent out of shape more than 3 inches. Bars in place with no bends more than 314 inch. Barç.are missing or entire barrier mrssrng. Bars in place according to design. Sars are loose and rust is causing 50%deferioratìon to any part of barrier. Barrier replnced or repaired to design siandarcls. lnlel/Outlet Pipe Debrìs barrier missing or not attâched toprpe Barrier fìrmiy attached to pip* You creaied this PDF Tram an applic*tion that is not licensed te pr¡nt io novaPilF printer {hftp:/lww$¡,l*v-çp,f¡f.ctiï)Attachment 5 No, 18 * Çatchbasin lnserts Yoluwe {/ * llunts/f'Trersf¡tzenl }lÍ¡li's - Ðec.emh*r 2{)14 4-.t I idaintenanæ Component [Þfêct ConditionE tftlhen Maintenance is l*leeded Results Expectad When Me¡ntenanc¿ is Performed Generai Sediment Accumulation When sediment forms å cap over the insert medìa ûf the insert and/or unit. No sedinlent cap on ihe insert media and its unit. Trâsh ãnd uuut rb Accumulation Trash and c{ebris accumulates on insert Ul llt t/, gdl¡l lg d UlUufiirg$/19!it'lLtlOlì. Trash and debris removed lrorn inseri unii. Runoff freeiy flows irrto catch basin. Medìa lnseri Not fremoving Oil äffluenl water lrom media insert has avisible sheen. gffluent water fram media insert is free of oiÌs and has na vìsible sheen. Media lnsert Wäter $aturated C*tch basin insert is saturãtsd with weter and no longer has the capacity to absorb. Remove and replace medìa insert Medía lnsert-ûil $aturated Media oil $aturated due to petrofeum spill that drains into catch basin. Remove and replace mediaiq^*rI tèçt t. Media lnsert Use Seyond Normal Product Life Mediä has been userl beyand the typical averåge lile of media inseri product. ñemove and replace media at regular inTervals, depending on rnsert produÇt. Ysu crested this flDË from an applieation that is ¡rat licensed to print to n*vaPDF printer ([:üp:ilw,.w:¡lÕväp{Lçsm)Attachment 5 C. GEOTË,CH REPORT lnsighi Fngíneering Co. - $Íormvuæter $ile Flan -45- 1?_!2{Jl2A17 Attachment 5 NR A TNF'ïET,}'} ÞESTGNS P. O. Box 164 Lk. Stevens, WA 98258-0164 {423) 335-'',t996 Rob Míchel clo Regent Construction, Inc 7305 Soundview Dr. Edmonds, \trA 98026 Dated 4/18/17 Soils Infiltration Report Site Location: 318 Howell St. Edmonds Tax Acct. # Very truly yours, Conrad C. Ëlledge Washington State Cerrified Designer #S100169 Snohomish Counfy Installer #f22A0 King County Inst¿ller #,ll{l.1.23 CCE:bto cc:file; Dear Rob, This letter is to provide results of the investigation requested by you for theabove referenced properry-. The purpose of this study was to estirnate theinfiltrative capacity of soils in the area of the proposed Bioretention pond intended to handle storm waters generated onlhe subject property. !n the 1?lh of ApnI,2017 we excavated test pits on the subject properfy: one inthe apx. center of the i5' &ont yard setback and one in the center oitir. backyard setback. Both test pits had water tables which preclude instaliation of on-site infiltrativefacilities. Thank you for your business and let me know if anyrhing furtþer is required. t; I à Page I of2 F tri rt Attachment 5 Attachment 6 Attachment 6 Attachment 6 Attachment 6 Attachment 6 Attachment 6 Attachment 6 Attachment 6 Attachment 6 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!505 424335 316 613519519510318 616 614 631 621654 610 622 630400 533 609 510 511 537 600 539 533531 545 520 530 534 544 554 558 654 543 541 539 533 527 521 515 507308 518555547 541 512504409403 402 272 437 271 400408 424 420 514 550 417 404 325 343337 275405303348 303 514428434430432 3RD AVE SWALNUT ST 5TH AVE SHOWELL WAY ERBEN DR HOMELAND D R H Project Location RS-6 BD3 P Zoning and Vicinity MapPLN20180067Howell Way Unit Lot Short Plat BD2 RM-2.4 R-95-1771 inch = 150 feetScale Attachment 7 CITY OF EDMONDS - PTANNING DIVISION STAFT COMMENT FORM E tw-rngineedng E] r¡r. El pw - Moinlenonce E aritaing Project Numbe PLN201 80067 Ânnlirrnf'c l\lrmo' r¡,t,,.!s¡¡r 318 HOWELL, LLC Property Location 3,18 HOWELL WAY Date Application Received 11.27.18 ate Application Routed 11.28.18 Zoning MULT| FAMTLY RESIDENTIAL (RM-2.4) Project Description 2LOT UNIT SUBDIVISION lf you have any questions or need clarification on this project, please contact: Responsible Staff KERNEN LIEN Exï. 1223 LEIF BJORBACKName of lndividual Submitting Comments BUILDING OFFICIAL f)are. 12111118Title E t how reviewed this tand use proposalfor my deportment ond I do not have ony comments. My deportment moy olso review this project during the building permit process (if applicoble) and reserves the right to provide odditionol comments ot thot t¡me. E t how reviewed this tand use proposolfor my deportment ond hove the following co m ments or conditio ns: Party wall construction is required to be two separate one-hour rated walls, and verified by survey that they are located each on their own separate lot Attachment 8 City of Edmonds Date: May 8, 2019 To: Kernen Lien, Environmental Programs Manager From: Jeanie McConnell, Engineering Program Manager Subject: PLN20180067, 2 lot short plat 318 Howell Way Engineering has reviewed the preliminary short plat application for the property at 318 Howell Way. The information provided indicates general engineering feasibility. Street Right-of-Way Dedication • Consistent with the City’s Official Street Map, a 5-ft street dedication to the City of Edmonds is required along the property frontage on Howell Way. Lot and Street Layout and Sidewalks: • The subject property is located on Howell Way and is adjacent to a public alley. During review of the building permit (BLD20170882) for the duplex recently constructed on the site, it was determined that access is to be from the alley. • Howell Way is a local street in the RM-2.4 zone. Edmonds Community Development Code 18.90.030 requires 7’-10’ wide sidewalks to be constructed along the property frontage. Consistent with this requirement, 7’ wide sidewalks with street trees were constructed along Howell Way. Typically, Engineering Requirements are established during preliminary review of a subdivision to clearly define conditions of approval. As the subject short plat is being completed following the recent construction of the duplex, all engineering requirements were addressed with the approval of building permit BLD20170882. As such, there are no engineering requirements and civil construction plans will not need to be submitted for review and approval prior to the applicant submitting for final plat approval. Thank you. MEMORANDUM ENGINEERING MEMO OF COMPLIANCE Attachment 9 Fl[E NO.: P1N20180067 Applicant: Howell LLC DECLARATION OF POSTING On the 28th day of December,2OtS, the attached Notice of Application was posted at the subject property, Civic Hall, Library and Public Safety buildings. l, Kernen Lien, hereby declare under penalty of perjury under the laws of the State of Washington that the foregoing is true and correct this 28th day of December,2018, at Edmonds, Washington Signed ò {BFP747893.DoC; 1\00006.900000\ }Attachment 10 FILE NO.: PLN20180067 Applicant: Howell LLC DECLARATION OF MAILING On the 28th day of December,2018, the attached Notice of Application was mailed by the City to property owners within 300 feet of the property that is the subject of the above-referenced application. I, Debbie Rothfus, hereby declare under penalty of perjury under the laws of the State of Washington that the foregoing is true and correct this 28th day of December, 2018, at Edmonds, Washington. Signed: { BFP747887.DOC; l\00006.900000\ }Attachment 10 c. 18 9s PROJECT DESCRIPTION PROJECT LOCATION NAME OF APPLICANT: FILE NUMBER: DATE OF APPLICATION: DATE OF COMPLETENESS: DATE OF PUBLIC NOÏICE: REQUESTED PERMIT: CITY OF EDMONDS NOTICE OF APPLICATION The applicant is proposing a unit lot subdivision for the Howell LLC Townhomes creating two unit lots with access of the adjacent alley. The townhomes currently under construction where reviewed and approved under building permit BLD2AfiO862. The site is zone Riv4-2.4 (Muiti-famiiy resicientiai; one ciweiiing unii permit 2,400 sq. ft. of lot area). 318 Howell Way, Edmonds, WA Tax Parcel Number 00409600101902 Rob Michel,318 Howell LLC P1N20180067 November 27,20L8 December 21,,2018 December 28,2018 Short Subdivision (Type ll-A Permit Process) None OTHER REQUIRED PERMITS: EXISTI NG ENVI RON MENTAL DOCUMENTS: Critical Area Determinat¡on, Storm Drainage Report COMMENTS ON PROPOSAL DUE:January tt,20t9 Any person has the right to comment on this application during public comment period, receive notice and participate in any hearings, and request a copy of the decis¡on on the application. The City may accept public comments at any time prior to the closing of the record of an open record predecision hearing, if any, or, if no open record predecision hearing is provided, prior to the decision on the project permit. Only parties of record as defined in ECDC 2O.O7.003 have standing to initiate an administrative appeal. lnformation on this development application can be viewed or obtained at the City of Edmonds Development Services Department, I2l - sth Ave North, Edmonds, WA 98020 between the hours of 8:00 A.M. and 4:30 P.M. Monday, Tuesday, Thursday and Friday; between the hours of 8:30 AM and Noon on Wednesday; or online through the City's website at https://permits.edmonds.wa.us/citizen through the Online Permits link. Search for permit P1N20180067. Kernen Lien, Environmental Programs Manager kernen.lien @edmondswa.gov 425-771-0220 CITY CONTACT: Attachment 10 ottN HOWELL WAY e€6{ 5 FÐOT üËOIC^NON TO CITY-----t 16.58 - fo(!) UJ:)z l.IJ 4Þq i¡tt(f eEolo*oo fIJ(J Éx:<ts 6 É)<.¿ t't tr{5Õbavl Êp('ob ?àl =lol BIttr æt I I - Iro iÉ(¡ E UJ){TÆ( FÂÊCIL 008727ð005t400 $Bså6'15t ıO.00 BUIT,ÞING LINE AT FOU|,¡ÛAîON (TTP) ¡t8f53'49'Ë. ö0.00 .5 .0 6.5 FT STORIi¡ DRAINÂËE FrùSEttENï LOTA ; 1 0,1' tû' ø*ça rl,tô€5¡ ú) 0' 10.0' Nrlc;o tr! Orê lo.o" (sLDG) _JtJ'-ru Lor s iiã uB Attachment 10 Bverett Daily Herald Affïdavit of Publication State of Washington I County of Snohomish )ss Dicy Sheppard being first duly sworn, upon ^^+L ,.1^^^--- --¡ ...'". tLor La/clre ic tlra lecqluotr¡ uvPvrvr 4^¡u rqJr. representative of the Everett Daily Herald a daily newspaper. The said newspaper is a legal newspaper by order of the superior court in the county in which it is published and is now and has been for more than six months prior to the date of the first publication of the Notice hereinafter referred to, published in the English language continually as a daily newspaper in Snohomish County, Washington and is and always has been printed in whole or part in the Everett Daily Herald and is of general circulation in said County, and is a legal newspaper, in accordance with the Chapter 99 of the Laws of 1921, as amended by Chapter 213, Laws of 1941, and approved as a legal newspaper by order of the Superior Court of Snohomish County, State of Washington, by order dated June 16, 1941, and that the annexed is a true copy of 8DH839302 PLN20180067 as it was published in the regular and entire issue of said paper and not as a supplement form thereof for a period of I issue(s), such publication commencing on 1212812018 and ending on 12128/2018 and that said newspaper was regularly distributed to its subscribers during all of said period. The amount of the fee such publication is s't0.52. Subscribed and sworn before me on this day ofPF f' Notary Public Washington. City of Edmonds - LEGÀL ADS | 141014 I 6 KERNEN LIEN and for the State NotarY Public State of Washington My Commissi JulY 30, on ExPires 2A22 AUBRËY KNAPP Attachment 10 Classified Proof CITY Publ¡shed: Dece¡nþeI 28, 241 8. Nov€mbêr 27 Oecamber Nono. Procegs) Programs ManagBr 8DH839302 Proofed by Sheppard, Dicy,12/2812018 08:57;56 am Page;2 Attachment 10 Attachment 11 Attachment 11 Attachment 11 Attachment 11 Attachment 11 Attachment 11 Attachment 11 Attachment 11 Attachment 11 Attachment 11 Attachment 11 Attachment 11 Attachment 11 Attachment 11 Attachment 11