BLD20161004_ENG2.pdf
CITY OF EDMONDS
PLAN REVIEW COMMENTS
ENGINEERING DIVISION
(425) 771-0220
City Website: www.edmondswa.gov
DATE:December 21, 2016
TO:Ben & Heather Swerk
Bswerk80@hotmail.com,heather.swerk@gmail.com
FROM:Jennifer Lambert
Jennifer.lambert@edmondswa.gov
RE:Application #: BLD20161004
Project: Swerk-Single Family Residence
Project Address: 18816 Olympic View Dr
During review of the above noted application, it was found that the following information, corrections,or
clarifications are needed. Reviews by other divisions, such as Planning, Building, or Fire may result in
additional comments. Please redline plans or submit three (3) sets of revised plans/documents with a written
response to each of the items below to a permit coordinator.
nd
Resubmittals can be made at the Development Services Department on the 2floor of City Hall. Permit
Center hours are M, T, Th & F from 8am-4:30pmand on Wednesdays from 8:30am-noon.
City of Edmonds handouts, standard details and development code can be referenced on the City website.
st
1Review –November4, 2016
nd
2Review –December21, 2016
SHEET C1 OF C4 (Stormwater Management Site Plan)
GENERAL
1)OK
2)12/21/16 –Comment was addressed; however, the lines are still faint. If it is easy to make the
proposed construction elementsclearer(i.e. making the proposed lines darker), please do so.
11/4/16 Comment: Clearly distinguish what will be installed with this project and what is currently
installed (i.e. different line types, bolding, etc.).
3)OK
General Notes
1)OK
Storm Drainage General Notes
1)OK
2)OK
WATER
1)
11/4/16 Comment -It appears that a fire sprinkler systemis required for this property. The applicant
will be required to pay for the new tap on the main and the new meter. This fee is $2970.00.
a.OK
b.12/21/16–It appears that the comment was intended to be addressed; however, the
water service line is not shown on the plans.
11/4/16Comment:Please show a 1-1/2” line to be installed from the back of themeter to
the house (as required for a combination fire and domestic service line).
c.12/21/16–The comment is stated but the water service line is not shown.
11/4/16 Comment: Please label the pipe material and note tracer wire to be installed on the
water service line.
2)12/21/16–The comment is stated but the water service line is not shown.
11/4/16 Comment: Show that there is a minimum of 3’ of horizontal separation between the water
and the dry utilities (i.e. power, phone, gas, cable, etc.).
3)OK
SEWER
1)OK
2)12/21/16–A note was added; however, the cleanout was not shown on the plans.Please show
the cleanout.
11/4/16Comment: Show a cleanout at the edge of easementand within 2’ of the structure.
3)OK
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4)12/21/16–Commentwas addressed; however, ABS is not permitted outside of 2’from
structure. The City requires the side sewer to be a gasketed pipe such as SDR 35. Please
revise the plans accordingly.
11/4/16 Comment: Label the pipe material and size.
STORM
1)OK
2)12/21/16–It was noted on the plans that the footing drains will discharge to theonsite
infiltration system; however, it does not appear that theonsite stormwater management
system was designed to accountfor theadditional water. Please revise the plans accordingly.
One option is to have the footing drains discharge to a separate system (i.e. drywell).
11/4/16 Comment: Showwhere the footing drains will discharge to. If the footing drains are to
discharge to the onsite stormwater management system, please address the allowance for the footing
drains in the design calculations.
3)OK
4)12/21/16 –Comment was partially addressed. Theproposed overflow path is running parallel
with the site not down the site. Please show that the overflowpathis maintainingthe natural
runoff flow path from the siteas it was prior to constructionand not negatively impacting the
neighboring properties. You will also need to clearlyshow theoverflowpath in the section
detailsfor the proposed facility.
11/4/16 Comment: Show the overflow path for the proposed stormwater management facilityand
clearly indicate/show that it will not negatively impact downstream properties.
5)OK
6)OK
st
1Review-11/4/16 comments are from the City of Edmonds stormwater consultant.
nd
2Review–12/21/16 comments are by Robert C Edwards, PE, Stormwater Engineer, City of
Edmonds
1)12/21/16 –Comments were not addressed.
11/4/16 Comment: The letter report (7/22/16) states that a treatment facility must be provided since
the total impervious area exceeds the 5,000 sf threshold; however, the total pollution-generating
impervious surface (PGIS) does not exceed the 5,000 sf threshold for Small Site Minimum
Requirement #6, so treatment is not required.
2)12/21/16 –Comments were not addressed.
Page 3of 6
11/4/16 Comment: The letter report (7/22/16) and plan set (8/2/16) describe a stormwater facility
that appears to be a rain garden stacked on top of an infiltration trench,which is not an approved
BMP in the 2005 Stormwater Management Manual for Western Washington (SWMMWW). Since
treatment is not required, it is recommended to simplify this design to either a rain garden or an
infiltration trench or to show the facilities in series, but not stacked on top of each other. The letter
report states that “This assemblage is commonly referred to as a rain garden, through there will be
no requirement for the intensive landscaping typical of such a facility, this being simply a BMP and
used primarily for percolation treatment of the driveway runoff.” This statement is incorrect and
appears to be mixing aspects of infiltration trenches and rain gardens. If a rain garden is selected,
vegetation would be required per the guidance in the2005 SWMMWW.
3)12/21/16 –Comments were not addressed.
11/4/16 Comments: The plan set (8/2/16) describes a bioswale in detail 300 and in the seeding mix
specified in detail 120. A bioswale (or biofiltration swale) is designed to be a flow-through water
quality treatment BMP, not an infiltration BMP.
4)OK
5)12/21/16–Comments were not addressed.
11/4/16 Comments: The letter report (7/22/16) and plan set (8/2/16) describes the compost-
amended soils requirement (BMP T5.13) instead of the bioretention soil mix required for
bioretention installations. The WWHM output report (7/13/16) also uses the “SMMWW 12 in/hr”
material type which is linked to the bioretention soil mix specifications, not BMP T5.13.
6)OK
7)12/21/16 –Comments b, e, and f were not addressed. Comments a, c, d, are OK.
11/4/16 Comments: The WWHM output report (7/13/16) contains the following
errors/discrepancies:
a.The Everett Rain Gage with a Precip Scale of 0.80 is used for sizing; however, the
Edmonds Stormwater Supplement requires the use of the Puget East 36 rain gage which
can be selected by checking "Use WS-DOT data" on the "Map Information" tab in
WWHM.
b.The pervious area is 0.08090 acres (3,524 sf) which is inconsistent with the 1,620sf
included in the letter report.
c.The infiltration rate is 100.
d.The riser height for the swale is 0.75 feet; however, the letter report specifies a 6-inch
ponding depth
e.The geotechnical site evaluation identifies the site soils as Class A soils; however, Class
C (till) soils are specified in the WWHM output report.
f.The pervious areas are modeled as pasture. If these areas will be standard
lawn/landscaping, they should be modeled as lawn.
***An alternative to the WWHMmodeling approach is to use the City’s simplified sizing (Handout
#E72B) to size either an infiltration trench or a bioretention cell.***
Page 4of 6
8)12/21/16 –Comments were not addressed.
11/4/16 Comments:WWHM2012 is the most recent and up-to-date version of the Western
Washington Hydrologic Model. Although not required, it is recommended for use over WWHM4
since it contains the latest updates from the model developer.
9)OK
10)OK
11)12/21/16 –Comment was not addressed.
11/4/16 Comments: The topographical contours are not labeled in the plan set (8/2/16).
12)OK
SHEET C2 OF C4 (Storm System Details)
1)As changes are made, please revise this plan sheet as needed.
SHEET C3OF C4 (TESC & Clearing Plan)
GENERAL
1)12/21/16 –Comment was partially addressed. Please reference the Edmonds Standard Detail.
11/4/16 Comment: Show the filter fence and reference the Edmonds Standard Detail E1.1.
2)OK
3)12/21/16 –Comment was partially addressed. Please reference the Edmonds Standard Detail.
11/4/16 Comment: Show the construction entrance and reference the Edmonds Standard Detail
E1.2.
4)12/21/16 –Comment was not addressed. The stormwater facility shall not be usedsediment
holding area.
11/4/16 Comment: Show protection fencing around any low impact stormwater facilitiesto prevent
disturbance of the area during other site construction activities.
5)OK
Permanent Stabilization Notes
Page 5of 6
1)12/21/16 –It appears that it was attempted to address the comment; however, the landscaping
should be completed as soon as disturbance to the soils are finished, not when the entire
construction project is completed. Please revise the note accordingly.
11/4/16 Comment: Note 1 –Please revise to state that seeding will occur as soon as disturbance of
the soils have been completed.
SHEET C4 OF C4 (Grading Plans)
1)As changes are made, please revise this plan sheet as needed.
2)OK
LANDSCAPE PLAN
1)OK
2)OK
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