Response to Eng Comments.pdfSubmittal To: City of Edmonds
Project:
541 3rd Ave N
Project Number
BLD20151312
Owner:
South Shore Retreat LLC
Revisions By:
Tim Gabelein, PE - Davido Consulting Group
Date Revised:
3/25/2016
Description:
City of Edmonds Review Comments dated March 25, 2016 and DCG responses
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March 25, 2016
Comment
Source/Location
Comment
Response
General:
1)
3/11/16 — Comment was partially addressed. However,
Existing striping and new striping are now shown. See Key Notes 4-6, 8,
striping will need to be changed due to the
and 9 on Sheet CO3.
reconfiguration of the driveway. Please show existing
striping verses new striping.
12/21/15 Comment: Show the existing striping along
the frontage and where striping will need to be replaced.
2)
When you total the impervious surfaces calculations they
The driveway square footage was incorrect on the previous plans and has
do not add up to 4,988 sqft. Please revise accordingly. If
been fixed on the revised plans. See Sheet CO2.
the total changes please revise all plans sheets
accordingly (including A2).
3)
Please do not show the trees that are to be removed.
Trees to be removed are only shown on the TESC Plan (Sheet C01). Sheet
Only show proposed trees or trees that are to remain.
CO2 shows proposed trees only.
4)
It was recently discovered that concrete exists under 3rd
It is now noted on Sheet CO3 that pavement restoration will be per onsite
Ave N. Roadway restoration will be determined at time
inspector's discretion and that 3rd Ave N conditions may include asphalt
of inspection. In previous restorations in this area, the
over concrete. See Key Notes 3 and 9 on Sheet CO3.
contractor was required to install native backfill and
approx. 10" of asphalt.
5)
Consistent with our phone conversation, if the utilities
As we discussed on the phone, the water and sewer connection locations
are installed as shown on the plans
in 3rd Ave N were switched. There is now one trench into the street shown
submitted 1/28/16, a grind and overlay will be required;
for both the storm and sewer. The water main is located a few feet into
such that all trenches are captured in one
the street and likely will not require concrete panel removal.
large patch. I suggest reviewing the utility locations to
see if you can combine utility installation to
allow for 1 trench patch within the roadway.
6)
Please provide a traffic control plan for the proposed
Traffic control plan to be provided by the architect.
work in 3rd Ave N.
Water:
1)
3/11/16 — Comment was addressed. This comment is
All minimum utility separations are met. In addition, we added notes for
remaining in case utilities are relocated as plans are
the contractor to maintain the required separations (see General Notes 2-4
revised.
on Sheet CO2).
12/21/15 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.). Currently
the gas is too close to the proposed water service line.
2)
3/11/16— Comment was addressed. This comment is
See response to above comment.
remaining in case utilities are relocated as
plans are revised.
12/21/15 Comment: Please keep in mind that there is a
requirement that there is a minimum of 10' of
horizontal separation between the water and the sewer
lines.
Sewer:
1)
No comments — Please make sure that as changes are
See response to above comments.
made, that the required minimum separation is being
met (3' from the dry utilities, l0' from the water, 5' from
storm).
Storm:
City of Edmonds Review Comments DCG, Inc. Page 1 of 4
March 25, 2016
Submittal To: City of Edmonds
Project: S41 3rd Ave N
Project Number BLD20151312
Owner: South Shore Retreat LLC
Revisions By: Tim Gabelein, PE - Davido Consulting Group
Date Revised: 3/25/2016
Description: City of Edmonds Review Comments dated March 25, 2016 and DCG responses
1)
3/11/16 — Comment was addressed. This comment is
All rim and invert elevations are shown on the plans.
remaining in case utilities are relocated as
plans are revised.
12/21/15 Comment: Please provide rim and invert
elevations for all catch basins and all pipes.
2)
_
3/11/16 Comment was partially addressed.
longer ted to the um but
a. The footing drains and yard drains are no ong routed pump
a. Confirm that the footing drain flows and yard drains
instead will be routed to a drywell in the back yard as discussed in a phone
flows are accounted for in the pump design.
conversation with Jennifer Lambert. See Key Note 26 on Sheet CO2.
b. If the pump design allows for the connection of
b. Footing drain and yard drains are no longer routed to the pump station.
groundwater, revise note 3 under the 'Drainage Notes'
Therefore, no revision to Note 3 under Drainage Notes is necessary.
to say "Footing drain and yard drains to discharge to the
c. Plans now shoe footing drains and yard drains discharging to a drywell
pump station (14).
(See Key Note 26 on Sheet CO2).
c. If the footing drains and yards drains cannot discharge
to the pump station, please show them discharging to a
separate system (i.e. drywell).
12/21/15 Comment: Show where 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)
Revise the notation for the 6" area drain located west of
Notation revised to say 6" OVERFLOW YARD DRAIN,
the home to clearly state that it is an
overflow yard drain.
4)
Storm lines must be connected at structures and be
The storm is now connected to the existing structure within 3rd Ave N. The
completed by the contractor (not the City of Edmonds).
storm line is now shown as angled within the ROW to make the connection
Please show connection to the existing catch basin. The
possible.
line may angle as needed. The catch basin may be
located in the curb line of the driveway.
5)
Clearly show the location of the alarm for the storm
The control panel/alarm is now clearly shown on the plans and is located
pump. The proposed location (from the detail on C05) of
on the south wall of the garage (see Key Note 27 on Sheet CO2). The
the alarm shows that the alarm may be easily damaged
Duplex Pump Station detail has been revised to note that the control panel
by vehicles.
will be located on the south wall of the garage. See Detail V on Sheet COS.
Stormwater
Comments from
H.arrer,a:
1)
The Drainage Narrative (1/25/16) includes detail on
The Drainage Narrative has been revised accordingly.
Minimum Requirement #3 - Source Control of Pollutants
in Appendix A; however, this minimum requirement is
not required for single family residential sites.
2)
On page 3 of the Drainage Narrative (1/25/16), the text
The infeasibility statement due to the requirement for flow control has
for Minimum Requirement #5 states that LID options
been removed. The report now states that "Low impact development
were deemed unsuitable due to the requirement for
options are not feasible onsite due to the lack of area for dispersion and
flow control. The intent of LID BMPs is to provide flow
poor onsite soils."
control via infiltration and dispersion. LID BMPs can also
be used to help meet or fully achieve flow control
requirements. I would recommend removing this
infeasibility statement. Poor onsite soils from the
geotechnical investigation is enough proof that LID BMPs
are not suitable for this site.
City of Edmonds Review Comments DCG, Inc. Page 2 of 4
March 25, 2016
Submittal To: City of Edmonds
Project:
541 3rd Ave N
Project Number
BLD20151312
Owner:
South Shore Retreat LLC
Revisions By:
Tim Gabelein, PE - Davido Consulting Group
Date Revised:
3/25/2016
Description:
City of Edmonds Review Comments dated March 25, 2016 and DCG responses
3)
On page 5 of the Drainage Narrative (1/25/16), the roof
Both the Drainage Narrative and WWHM report have been revised to
area is listed as 0.09 acres; however, the WWHM report
show the correct areas for the roof and driveway, which are 0.082 acres
lists 0.08 acres. Please update for consistency between
and 0.023 acres, respectively.
the narrative and the model output report.
4)
Page 2 of the WWHM report lists the WWHM version as
The WWHM version has been updated to Version 4.2.11(2015/11/13) and
2014/04/24. There have been several model updates
a new report has been generated. See the appendices in the Drainage
since that time. The current version of the model is
Narrative for the updated WWHM report.
Version 4.2.11(2015-11-13):
http://www.ecy.wa.gov/Programs/wq/stormwater/wwh
entraining/index.html. Please revise accordingly.
5)
Terminology in the Drainage Narrative (1/25/16) and
The Drainage Narrative and plans have been revised to consistently use the
plans (Sheet CO2) is inconsistent - detention pipe,
term "detention pipe".
detention tank, and detention system. Please select a
single term (detention pipe) for consistency throughout
the narrative and plans.
6)
The Drainage & Utility Plan (Sheet CO2, 1/25/16) lists a
Drainage Note 4 on Sheet CO2 has been revised to say "DETENTION PIPE
4" sediment depth as the maintenance trigger in Note 4.
SHALL BE CHECKED ANNUALLY FOR SEDIMENTATION ACCUMULATION. IF
The actual criteria in Appendix B (0&M) of the Drainage
ACCUMULATED SEDIMENT DEPTH EXCEEDS 3.6" FOR 1/2 LENGTH OF THE
Narrative (1/25/16) should be calculated as 3.6" for half
DETENTION PIPE OR 5.4" AT ANY POINT, MAINTENANCE SHALL BE
the length of the pipe or 5.4" at any point. Please revise
PROVIDED FOR SEDIMENT REMOVAL (I.I. VACTOR TRUCK)."
accordingly.
7)
The Drainage Narrative (1/25/16) states that the 100-
The revised WWHM report yielded a 100 -year, 24-hour design storm of
year, 24-hour design storm is 40 GPM; however, based
0.091194-cfs or 40.93 GPM. The Drainage Narrative has been revised
on the value in the WWHM modeling report (0.096554
accordingly.
cfs), this should actually be 43.34 GPM. Please revise
accordingly.
8)
There is not any discussion on how the pumps will
A discussion on how the pumps will operate has been added to the
alternate in the Drainage Narrative (1/25/16). If they
Drainage Narrative. The pump system will consist of a 3 -float system. The
both operate on floats, will they both turn on at the
bottom float will turn all pumps off, the middle float will activate one
same time, or how will they alternate? Is there a
pump, and the highest float will activate the 2nd pump and the alarm. The
controller? The graph appears to show an option for
pumps will alternate so that only one pump is activated for the majority of
both pumps to operate at the same time — is that an
storms. When one pump turns off, the other pump will turn on during the
intended function? The system curve does not extend far
next storm. A control panel will control the pumps, floats, and alarm. See
enough to cross the dual pump curve, but appears that it
the revised Drainage Narrative and appendices for additional information.
would cross—70gpm.
9)
The system curve crosses the pump curve at —50gpm for
A smaller pump is specified (1/3HP) and is the recommended pump per
the HW TDH, and —45gpm for the LW TDH in Appendix E
the pump supplier (HD Fowler) for these operating conditions. The Pump
of the Drainage Narrative (1/25/16). This is above the
System Curve has been revised accordingly. The system curve crosses the
100 -yr design flow of 40gpm. Please revise accordingly.
pump curve at —43gpm for the HW TDH and —37gpm for the LW TDH. The
LW TDH is now below the 100 -yr design flow of 40.93 GPM, while the HW
TDH is slightly higher.
10)
The overflow path if the pumps fail is described in the
The overflow path description has been added to the Drainage Narrative.
response to comments, but should be added to the
Drainage Narrative (1/25/16) since this does not clearly
show up on the plan set and is not currently discussed in
the Drainage Narrative.
Dry Utilities:
3)
3/11/16 — Comment was addressed. This comment is
Utility separations have been maintained.
remaining in case utilities are relocated as plans are
revised.
12/21/15 Comment: Please show all proposed dry
utilities (gas, phone, cable, etc.) on the plans so that
utility separation can be verified. Minimum of 3'
horizontal separation between the dry utilities and
water, sewer, storm is required.
City of Edmonds Review Comments DCG, Inc. Page 3 of 4
March 25, 2016
Submittal To: City of Edmonds
Project:
541 3rd Ave N
Project Number
BLD20151312
Owner:
South Shore Retreat LLC
Revisions By:
Tim Gabelein, PE - Davido Consulting Group
Date Revised:
3/25/2016
Description:
City of Edmonds Review Comments dated March 25, 2016 and DCG responses
Grading Plan &
Driveway Profile
rc03)
1)
The driveway cannot exceed 14% slope (per Edmonds
The driveway has been revised to be 14% max slope (see the Driveway
Community and Development Code 18.80.060). Please
Profile on Sheet CO3).
revise accordingly.
Details (C05):
1)
1) Pump General Notes
Pump notes 1 and 8 have been removed.
a. Remove note #1— Storm is not permitted to connect
to sewer.
b. Remove note #8 —The pipe must be inspected prior
to backfill.
2)
Provide float elevations in the detail.
A pump control schematic showing the float elevations has been added
above the Duplex Pump Station Detail on Sheet COS.
3)
The detail for the pump system states that the alarm is
The note to the alarm/ control panel on the Duplex Pump Station detail has
shown on C04; however, this sheet is for details. Should
been revised to say "CONTROL PANEL TO BE LOCATED ON SOUTH WALL
this be revised to say sheet CO2? Please revise the note
OF GARAGE. SEE SHEET CO2 FOR LOCATION."
accordingly.
4)
Please revise the pump station details to be consistent
The pump station detail has been revised to be consistent with the City's
with the City's stormwater pump policy and Standard
stormwater pump policy and Standard Detail E6.7 and includes rails and
detail E6.7 (Sewer grinder pump). For example, show
vents. An antiflotation device is not necessary since the pumps will be
antiflotation devices, rails, vent, etc. Make sure that the
house in a concrete catch basin (54" diameter). The manhole lid provides a
design shows that they system can be maintained (for
24" opening for access/maintenance, which is the same size lid specified in
example the standard detail E6.7 shows that the entire
Standard Detail E6.7.
lid can be removed for a maintenance where a manhole
lid does not allow for this.
5)
Please provide approx. pipe lengths, types, sizes, etc. to
Please
Pipe lengths, types, and sizes have been added to the Duplex Pump Station
pump details.
detail.
City of Edmonds Review Comments DCG, Inc. Page 4 of 4