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bld20120661-Swedish_Medical_Ctr-E1.pdf CITY OF EDMONDS PLAN REVIEW COMMENTS ENGINEERING DIVISION (425) 771-0220 City Website: www.edmondswa.gov DATE:September 11, 2012 TO:Brad Hinthorne Brad.hinthorne@perkinswill.com FROM:Jeanie McConnell, Engineering Program Manager RE:Application#:bld20120661 Project:Swedish Medical Center Project Address: 21704 Highway 99 During review of the above noted application, it was found that the following information, corrections, or clarifications are needed. Please redline plans or submit three (3) sets of revised plans/documents with a written response to each of the items below to Linda Thornquist. City of Edmonds handouts,standard detailsand development codecan be referenced on the City website. GENERAL 1.Please provide an itemized engineers cost estimate, including units and unit prices,for both on- site and off-site (right-of-way) improvements, including traffic control.The City recommends use of the King County Site Improvement Bond Quantity Worksheet. A bond is required to be placed for all right-of-way improvements. The amount of the bond o will be based on 120% of the City approved estimate for all right-of-way improvements. The City will inform you of the appropriate bond amount after review of the cost estimate. Bond forms can be obtained from Marie Harrison, Permit Coordinator –425-771-0220 or Harrison@ci.edmonds.wa.us Inspection fees for this project will be calculated at 2.2% of the 120% City approved o estimate for all improvements. As inspection fees were paid under the previous permit and some but not all of the improvements were installed, it will be necessary for you to clearly outline this with your submittal so it can be determined what additional inspection fees are due. 2.A right-of-way construction permit was issued in conjunction with the previous building permit for the temporary curb cut on Highway 99 and restoration of such. This permit was issued to Skanska USA Building Inc. and is set to expire December 5, 2012. It appears as though Skanska is still the general contractor for the project, in which case wecan work with you on the permit expiration. If there will be a new contractor then a new permit will need to be issued. 3.Submit a traffic control plan for utility connections on Hwy 99. 4.I did not find storm detention vault structural calcs in the submittal. Were they submitted? If not, please submit for review and approval. The vault may be sent out for peer review. bld20120661-Swedish_Medical_Ctr-E1.docPage 1of 6 STORMWATER MANAGEMENT REPORT Review of the Drainage Report dated August 2012 was completed by Stormwater Engineer Jerry Shuster. If you have specific questions regarding these comments please contact Jerry directly by phone at 425-771-0220 or by email at jerry.shuster@edmondswa.gov GENERAL 1.Indicate which parts of the stormwater system installed under the previous permit will be “reused” in the design (if any). Conversely, indicate what parts constructed under the previous permit will be demolished with this project. 2.Provide a figure that shows the delineation of subbasins within the projectsite that flow to each stormwater facility (raingarden, vaults & ponds) and the amount of impervious and pervious area post-development. This should include tributary areas to the existing stormwater systems on the Swedish site.These were provided in Appendix D (Figures 1-3) in the Drainage Report dated November 2011 for the previous incarnation of this project.Update the figures to reflect the new proposed project. Page 4 –Runoff Treatment 1.The discussion of runoff treatment should follow the procedure in Appendix I, Section 4.6, of the Western Washington Phase II Municipal Stormwater Permit.The discussion should include an evaluation for need for oil control and enhanced treatment.Also, add a sentence that states that since the water quality treatment facility is downstream of the detention vault, it was designed to the full 2-year release rate from the detention facility. 2.The existing detention vault behind the proposed building was installed in 1999. The approved drawings for that vault show 150lineal feet of bioswale (1.5 ft wide @ 3.5%) along the north property line at the east end of the site.This bioswale is the approved water quality element for this detention system.The current set of drawings does not show this bioswale and it unclear from the drawings where the discharge from this 1999 vault day lights.The design must include this original bioswale or an approved equivalent alternatemeans of treating the discharge from the 1999 vault. Page 5 –Flow Control 1.The site is a Large Site Project subject to the requirements in Appendix I, Section 4.6, of the Western Washington Phase II Municipal Stormwater Permit. The predevelopment condition for the entire site should be the forested condition (including “Landscape Pond Basins”) and the criteria for compliance is the Standard Flow Control Requirement in Appendix I, Section 4.7 of the Western Washington Phase II Municipal Stormwater Permit.The entire site is one threshold discharge area with a point of compliance at the northeast corner.There are several options for modeling the landscape/pond areas located east and south of the proposed parking area such as: a.Keep the ponds, but size them using the predevelopment condition as “forested” and post development condition as “lawn” for their subbasin areas. The ponds must be sized to meet the Ecology duration standard. b.Remove the ponds and landscape the area using Ecology BMP T5.13 –Post Construction Quality and Depth.This area with the amended soil can be modeled as “pasture” ina bypass basin and the vault enlarged accordingly such that the Ecology duration standard is met at the point of compliance. Page 2of 6 Appendix D –“Raingarden & Vault Model –Mitigated Scenario –Raingarden 1.The outlet structure is modeled as a “Riser Outlet Structure.”The model is looking at the diameter of a round standpipe at a given elevation.The outlet is a 20x24 inch catch basin with a rectangular beehive grate.Provide the open area of the beehive grate and make it an equivalent to the area of round standpipe.Forexample, if the beehive has 2 square feet of open area, this is equivalent to a round standpipe 19.2 inches in diameter.Re-run the model with the revised parameters. 2.The plans show a6” diameter perforated underdrain for the rain garden.The underdrainis modeled with an Orifice Diameter= 0, meaning there are no opening in the pipe (model shows “Flow Through Underdrain” = 0 ac-ft).This modeling is not representative of the design please re-evaluate.By modeling the underdrain correctly this will likely change the amount infiltrated and outflow from the rain garden that will affect the vault sizing.Also, this model run shows 62.55% infiltration for this scenario.Later on in this Appendix, the Stage-Storage-Discharge table (“Landscape Swale Hydraulic Table”) indicates zero cfs infiltration for all stages.Please re-evaluate. 3.The modeling shows element “RAINGARDEN SufaceEN.” Please explain this element and how it is used in the modeling. Appendix E –Pond Calculations 1.See “Page 5 –Flow Control” comments above. SHEET C-110–GENERAL NOTES 1.Revise General Notes to include compaction testing requirements for trench work in Highway 99. Compaction tests shall be performed and test results indicating a minimum 95% compaction shall be submitted to the City for approval prior to asphalt restoration. 2.Please revise Construction Sequence Note #10 to also state disturbed soils shall be compost amended per Chapter 5 of the Stormwater Manual. 3.Revise Water Service Note #1 to callout a requirement for granular sand surrounding (above and below) the domestic water line. SHEET C-200–DEMOLITION & TESC PLAN 1.Along with note for temporary driveway, please note that the driveway shall be removed and replaced prior to project completion. 2.Add signage visible from Hwy 99 to clearly indicate the truck access so the Radia approach isn’t used for construction access. 3.A silt fence is shown at the west end of the existing Radia parking lot in a location that doesn’t allow for an appropriate vehicle turnaround. Place silt fence, chain link fence, or other barrier in a location that allows for the western most parking stalls a minimum 10-foot area to turn around. It is understood that the last couple stalls in the lot may not remain accessible during portions of the constructionactivity. The fence or barrier shall be adjusted accordingly. SHEET C-231–TESC DETAILS 1.Detail 7 is notreferenced on Sheet C-200. Will this pump be installed? Page 3of 6 SHEET C-300–PAVING & HORIZONTAL CONTROL PLAN 1.In the area of the new parking lot and building, please remove the existing parking lot layer. 2.Add callout, reference detail and note signage requirements as appropriate for the one-way traffic barrier to be placed on the southwest side of the site. 3.The turnaround area in the parking lot just southof the building shall extend a minimum of 10- feet west of the last stalls in the lot. 4.Will signage be placed indicated the drop off zone and parking restrictions? Please add detail for signage as appropriate. 5.It appears as though a new sign is being shown on the north side of the Radia driveway approach. Please confirm and add note that sign is to be approved under separate permit. 6.Add callouts for walls or include in the legend. 7.Add reference to thewalldetails provided within the plan set. 8.Clearly indicate location of trash enclosure and reference pertinent construction details. 9.Please label the two “structures” on the west side of the building near the pedestrian walkway and exit door. Are these utility vaults? Are the above grade of flush mounted? 10.Callout requirement to replace curb/gutter and sidewalk improvements along Hwy 99 frontage consistent with WSDOT standards for curb/gutter and City standard detail E2.13 for sidewalk. Incorporate standard details into plan set. SHEET C-330–PAVING DETAILS 1.Detail 3 is not referenced on Sheet C-300. Please remove detail or show crosswalk location within the plan set. 2.In area of new parking lot, storm infrastructure and building please remove “existing facilities” plan layer. 3.Plans indicate connection of the foundation drains to the detention vault. Please confirm the vault has been sized to accept theadditional flows (if any). 4.Label Pond 1 and Pond 2 and reference control structure details for each found on Sheet C-441. into 5.Please indicate how stormwater flows will discharge Pond 1 (the southern pond). 6.Label the vault and reference the detail provided on sheet C-450. 7.Label the vault control structure. 8.Label the rain garden and reference detail provided on sheet C-410. 9.The access drive shown on the south side of the property from the new parking lot to the southwest side of the existing Radia building doesn’t appear to match into the existing concrete area shown on the Radia property.Will the concrete area be widened to match into the new asphalt? 10.Please indicate where stormwater runoff from the SE corner of the south parking will flow to. It appears as though a small section will be directed onto the Radia site. SHEET C-410–RAIN GARDEN PLAN 1.Please include specs for the rip-rap dissipator pads 2.AddRIM elevation at Type I basin. Page 4of 6 SHEET C-420–GRADING SECTIONS 1.Details 2 & 4 –please add drain rock, soil and seed specifications where appropriate. Callout depths as well. Please also indicate plant species to be placed in the rain garden. 2.Detail 3 -Per this detail the parking lot places a surcharge on the wall. Please provide engineered calculations for the design of this wall and any other walls in the design that support a surcharge. SHEET C-430–STORM DRAIN PROFILES 1.Detail A – a.Callout pipe material, lineal footage and slope. b.CB 09 indicates a 6” and 12” pipe, but both pipes connected to this basin are 12”. Please revise. 2.Detail B – a.Callout pipe material b.Please confirm that the 12” pipe i.e. callout at CB’s 02 and 03 are for in and out pipes. 3.Detail C – a.Callout pipe material, lineal footage and slope for the section of storm pipe between the concrete pipe and CB-05. b.Callout outlet pipe i.e.at CB-11 4.Detail D – a.The WQ unit indicates (4) solid checker plate covers, but the plans show 3. Please revise accordingly. b.Callout outlet pipe i.e. at CB-11 SHEET C-440–STORM DRAIN DETAILS 1.The manhole details provided are for sewer manholes. Please revise to show storm manholes without channeling. 2.Add note that steps shall be polypropylene. SHEETC-441–STORM DRAIN DETAILS 1.Details 1 and 3 reference sheet C-510, but sheet C-510 isn’t included in the plan set. Should the reference be C-400? SHEET C-450–DETENTION VAULT DETAILS 1.Show outfall from Kristar WQ unit. 2.Provide and reference details for Kristar WQ unit within plan set. SHEET C-451–DETENTION VAULT DETAILS 1.Detail C –Flow Control Structure: Please add note that shear gate handle shall hook on ladder step in closed position. Page 5of 6 SHEETC-500–UTILITY PLAN 1.The DCDA and vault shall be located within 10-feet of the Hwy 99 property line. The domestic water meter shall be located on the ROW side of the property line (outside of the sidewalk) with the hotbox on private property immediately after. With this change no public easement will be provided.Please revise plans accordingly. 2.Revise plans to show both the domestic and fireline taps off the watermain in Highway 99. Reference and include in plan set City standard detail E7.18.1. 3.Trench in Highway 99 shall be restored to City standards –please reference and incorporate into plan set standard detail E4.2. 4.Show curb/gutter and sidewalk removal and replacement as needed for this utility connection. 5.Add reference to details 1 and 2 on sheet C-520 and Detail 1 on sheet C-521 as they pertain to the DCDA and water meter. 6.Please include in plan set and reference City standard detail E7.11 for RPBA in a hotbox. 7.The water main on Hwy 99 is 8” DIP. Please revise callout of fittings at the valve cluster connection on Highway 99 to the following: a.(1) 8”x8”DI tee (FLxFLxFL) b.(2) 8” MJ Couplers c.(3) 8” Gate Valve (MJxFL) 8.Revise the fittings at the fire hydrant connection as follows: a.(1) 8” x 6” DI Tee (FLxFLxFL) b.(1) 6” Gate Valve (MJxFL) c.(1) 8” Gate Valve (MJxFL) d.(1) 8” MJ x FL Adapter 9.Please confirm water system pipe sizing … Can the fire line be reduced to 4” after the hydrant? Can the domestic service and meter be reduced to 1 ½” or 1”? 10.2–45degree bends should be used in main line instead of 90degree bends. 11.DIP classification should say Class 52. It isunclear what CL200 is? 12.For the sanitary sewer system reference details provided on sheet C-522. 13.Callout existing water service to Radia. 14.Show location of existing sanitary side sewer to Radia. 15.An existing easement legend has been provided, but it is unclear where each of these easements exist on the property. Please identify pertinent easements on the plan set. Please contact me at 425-771-0220 or by e-mail at mcconnell@ci.edmonds.wa.usif you have specific questions regarding these plan corrections. Page 6of 6