4621_001.pdfINSIGHT ENGINEERING CO.
September 26, 2018
T 'Amb.-rf
121 5th Ave NE
Edmonds, WA 98020
(425) 771-0220
Re: Zimmerman Edmonds SFR — BLD20180576
IECO No. 17-0858
Dear Jennifer,
The project referenced above is revised in response to the review comments dated September 11,
2018. The review comments are numbered on the letter and have been addressed in italics as
follows:
Sheet C1 of 2 (Drainage and Utility Plan)
1) 9/11/18 — comment was addressed; however, it is unclear as to what areas of the roof
line will discharge to the proposed stormwater management system. If it is not
possible to isolate the new roof line from the existing, then the stormwater runoff
from the existing will need to be included in the stormwater calculations. The
stormwater management system will need to be designed for all impervious areas
that discharged to it.
The stormwater detention system was designed with an additional 25% impervious of the
existing home. The remainder of the existing home will continue to be directed to the
existing down spouts on the north and northwestern portion of the home.
6/5/18 Comment: The plans are unclear as to exactly what is new/replaced impervious
and what is proposed impervious surface areas. If the existing impervious areas are being
removed to bare soils (roof and foundation) and replaced with new impervious surfaces,
this area will be counted towards new/replaced impervious areas.
a. Please clearly show what is new/replaced (i.e. hatching, etc.).
Refer to the revised hatching on sheet C1.
PO Box 1478 * Everett, WA 98206 * Phone: (425) 303-9363
Fax: (425) 303-9362 * Email:info@insightengineering.net
b. Please clearly distinguish between new/replaced and 2nd story additions that do
not count as new/replaced impervious areas.
Refer to the figure on sheet Cl for the new/replaced areas.
c. Please clearly show areas where new/replaced roof overhang is to be installed
over existing pervious areas.
Refer to thefigure on sheet Cl for the new/replaced areas.
d. It is stated that the driveway is to remain; however, the plans indicate that a large
portion will be replaced with storm line improvements. The existing driveway
areas outside of the replaced area seem to be poor condition and unlikely to be
preserved. Any portion of the driveway outside of what is currently shown on the
plans to be replaced, will count as replaced impervious area. If this increases the
new/replaced impervious area to 2000sf or greater, a stormwater management
system will be required.
Refer to thefigure on sheet C1 for the new/replaced areas. The driveway is being
replaced and has been accountedfor in the calculations.
2) OK
3) 9/11/18 - Comment was addressed; however, please label the overhang as existing.
6/5/18 Comment: The project is proposing to add foundation to the existing garage;
however it appears that a portion of the existing garage and/or roof overhang is
encroaching into the City right-of-way. Encroachment into the right-of-way is not
approved; therefore, please confirm that no portion of the existing encroachment will be
enclosed or expanded upon.
a. Please note that the City will not approve any repairs to the retaining walls,
fences, roof overhangs, and shed that is located within the City right-of-way.
When those structures need to be replaced or as otherwise directed by the City,
they will need to be located on private property.
Overhang has been shown as existing.
4) 9/11/18 — Comment was not addressed. Please see comments by the City's
Stormwater Engineer.
6/5/18 Comment: The City's GIS system shows that there are stormwater flows on the
subject site. Please show the stormwater on the plans if they exist.
PO Box 1478 # Everett, WA 98206 # Phone: (425) 303-9363
Fax: (425) 303-9362 # Email:info@insightengineering.net
The stormwater systems have been updated.
Sheet C2 of 2 (GradijiL, and TESC Plan)
1) 9/11/18 — Comment was not addressed.
6/5/18 Comment: Show the stormwater as stated above in #4 and any TESC needed
to protect the stormwater flows.
Although I do not agree with the city's assessment to protect the stormwater, silt
fence has been added to the perimeter of the construction flows.
2) OK
3) 9/11/18 — Comment was not addressed. Please see comments by the City's
Stormwater Engineer.
6/5/18 Comment: Please show the location of the silt fence and reference the City
standard detail.
Siltfence has been added.
4) OK
Please feel free to contact me with any questions or comments you may have.
Sincerely,
A
S�,� X"", /Zzz
rian Kalab, P.E.
PO Box 1478 * Everett, WA 98206 # Phone: (425) 303-9363
Fax: (425) 303-9362 * Email:info@insightengineering.net