HomeMy WebLinkAboutPermit File BLD-2021-0029 3708 Leeward Lane (3) tT Q�OR CODEco
�'� i �h ' �� � Y e�2 Storm Water Drainage Report
7011311, Minimum Requirements 2
Gj 4„v 1891Q,4 ENGINEERING DEPARTMENT
CO 1 � 904 6th Street Anacortes, WA 98221
www.anacorteswa.gov
Official Use Only: (Information to Inspectors)
Required Storm Water Facility and other related requirements:
Sediment transport potential score of 225, High.
Project Address: 3708 Leeward Lane Submittal Date: 1/6/2021
Parcel Number: P133206 Revision Number:
Permit Number: Reviewer: Rob F.
Acceptance Date (COA): 1/22/2021
FRONT OF REPORT:
Submittal Checklist: (All items listed below are required for a complete submittal)
o Cover Sheet (Preparer to Provide): Project title, Location, Revision dates, Engineer's Stamp
o TAB 2: Minimum Requirement#2 — Construction Stormwater Pollution Prevention (SWPP)
o APPENDIX 1 - Survey performed by a Professional Land Surveyor
o APPENDIX 2 - Soils Analysis (Volume 1, Chapter 3.1.1)
o APPENDIX 3 - Model Soil Management Plan for BMP T5.13
o APPENDIX 4 - Determining Construction Site Sediment Damage Potential (Appendix 7)
o APPENDIX 5 - Site Plan with all applicable information (Minimum Size 11x17 — 30 scale)
o APPENDIX 6 - Documented Site Photos (North, South, East and West)
o APPENDIX 7 - Drainage BMP Facility Maintenance Covenant, if applicable. To be recorded prior to the
Temporary Certificate of Occupancy, Certificate of Occupancy or Final Acceptance.
Stormwater Management Requirements:
o Refer to the 2012\14 Department of Ecology Manual, as amended in 2014 for further required
information.
o See also, City of Anacortes Municipal Code 19.76 for additional information
o See also, current Engineering Development Standards, Chapter 2- Storm Drainage for additional
information.
Project Description and Summary:
Summar Table
Existing Proposed
Development Type Residential
Number of Lots 1
Lot Acreage in SF 17,788
Soil Type(s) OL,SM, SM/ML
Site Sediment Transport Score (High\Low) >100
Depth to Ground Water Table (Feet and Inches) See Geo Report
(See completed Soils Analysis (Volume 1, Chapter 3.1.1)
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
Infiltration Rate during Rainy Season (Inch\Per Hour) See Geo Report
Impervious Surface (on-site) 1,371 sf 4,885 sf
Impervious Surface (off-site)
New and Replaced Hard Surface Total (SF) 4,885 sf
Lot Coverage (Percentage) 35%
BMP (Required Minimum Requirement 5) BMP T5.13 Post Construction Soils
Water Quality Method (Minimum Requirement 6)
Water Quantity Method (Minimum Requirement 7)
Existing Site Conditions Summary:
(Additionally, provide information on previous permits, if any, like Grade and Fill, Clear and Grade, topography,
vegetation, drainage, Critical Areas adjacent to the site and how it may affect this project if soils are disturbed,
Soils Type (Included in Soils Analysis Report), Erosion Problem Areas, Construction PhasinglSequence)
• The site was developed under the Leeward Landing PUD, which has all the appropriate permits and
has been accepted by the City of Anacortes Council and has been recorded.
• The site is sloping mostly from the South side of the site to the North side. The average sloping grade is
around 14.68% for most of the lot with steeper slopes intermittently near the road and near the top of
bank.
• The site is part of of a common plan development for Leeward Landing PUD. The report is part of the
recorded subdivision and covered in Minimum Requirements 1,3,4,5,6,7,8,and 9 for each lot. This
project is submitting Minimum Requirement 2.
• A soils analysis was done for this site and has been submitted.
• Construction Plan Sequencing (Note: sequence may not fall in this order, but close)
o Installation of Erosion and Sedimentation BMP's.
o Minor rock excavation work to ensure compliance with required BMP's under Minimum
Requirement 5 and 6.
o Installation of the footings and foundations.
o Construction of the home.
o Connection of the utilities to the home.
o Installation of MR#5 required BMP's
o Backfill of site with BMP T5.15 Post Construction Soils, Landscaping, driveway, driveway
access. See Appendix- Model Soil Management Plan for BMP T5.13
Developed Conditions Summary:
(Additionally, to be shown on the site plan. Identify cut and fill areas, proposed slopes of all hard
surfaces , proposed contours) see site plan
Drainage Basin (2007 Storm Comp Plan — City website\publicworks\engineering\comprehensive plans):
What Drainage Basin are you in? _Between G7 & G8_ Identify any downstream drainage issues (Storm Comp
Plan: _Unknown_ If so, describe: _On the Storm Water Comprehensive Plan, it is unclear what basin this
property is in._
Complete the Applicability Requirements — Flow Chart (Figure 1-2.4.1 Attached, Figure 1-2.4.2 Attached
and Figure 1-2.5.1 Attached)
- Highlight the path and attach
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
Start Here
1
Does the site have 35% Yef �.ee Redevelopment Minimu—
or more of existing I► Requirements and Flow Cha--
impervious coverage- (Figure I-2.4.2).
No
Does the project convert 34
• acres or more of vegetal on to
Does the project res. lawn or landscaped a re,s, or
5.000 square feet. No convert 2.5 acres - --�.re of
I greater, of new plus ► native vegetation to pasture?
replaoed hard surface - - —
area?
No
Yes _ , _
Yes Does the project result in 2.000
T 77uare feet, or greater, of new p►i
4
All Minimum Requirements -solaced hard surface area?
apply to the new and replaced
hard surfaces and converted
vegetation areas. Yes No
f
Does the project have land
Minimum Requirements #1 disturbing activities of 7.000
through #5 apply to the new YeS square feet or greater?
and replaced hard surfaces
and the land disturbed. No
y
All minimum req. are taken care of by Minimum Requirement#2
common plan of development. Only applies.
minimum req. #2 is needed.
Figure I-2.4. -1
Flow Chart for Determining Requirements for
New Development
DEPARTMENT OF Revised June2 1E
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=late o' wasnric,ton r'iItat?or ofllaolPty. and disclaimer.
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TAB 2 (MINIMUM REQUIREMENT #2)
• 1-2.5.2 Minimum Requirement#2 — Construction Stormwater Pollution Prevention Plan (SWPP)
- All projects are required to complete Minimum Requirement 2.
- Refer to the 13 Elements of the SWPP (See document below, complete and attach)
- See attached Table 4.1.1, Table 4.2.1 and Table
- Provide Engineering Calculations as an attachment for Sediment Ponds\Traps, Diversions,
Waterways and Runoff/Stormwater Detention Calculations.
• The site was developed under the Leeward Landing PUD, which has all the appropriate permits and
has been accepted by the City of Anacortes Council and has been recorded.
• The site is sloping mostly from the South side of the site to the North side. The average sloping grade is
around 14.68% for most of the lot with steeper slopes intermittently near the road and near the top of
bank.
• The site is part of of a common plan development for Leeward Landing PUD. The report is part of the
recorded subdivision and covered in Minimum Requirements 1,3,4,5,6,7,8,and 9 for each lot. This
project is submitting Minimum Requirement 2.
• A soils analysis was done for this site and has been submitted.
• Construction Plan Sequencing (Note: sequence may not fall in this order, but close)
o Installation of Erosion and Sedimentation BMP's.
o Minor rock excavation work to ensure compliance with required BMP's under Minimum
Requirement 5 and 6.
o Installation of the footings and foundations.
o Construction of the home.
o Connection of the utilities to the home.
o Installation of MR#5 required BMP's
o Backfill of site with BMP T5.15 Post Construction Soils, Landscaping, driveway, driveway
access. See Appendix- Model Soil Management Plan for BMP T5.13
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
Table 4.1.1 Source Control BMP's by SWPPP Element
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
Element#1 Element#2 Element#5 Element#6 Element#9 Element#11 Element#12 Element#13
BMP or Element Name Preserve Establish Stabilize Protect Control Maintain Manage the Protect Low
VegetatbnlMark Construction Soils Slopes Pollutants BM Ps Project Impact
Clearing Limits _ Access - _ Development
BMP C101: Preserving Natural Vegetation V
BMP C102:Buffer Zones V V
BMP C103:High Visibility Plastic or Metal V V
Fence
•
BMP C105: Stabilized Construction V
Entrance/Exit
BMP C106: Wheel Wash V
BMP C107: Construction Road/Parking V
Area Stabilization
BMP C120:Temporary and Permanent V V
Seeding
BMP C121: Mulching V V
BMP C122: Nets and Blankets V V
BMP C123: Plastic Covering V
BMP C124: Sodding V
BMP C125: Topsoiling/Composting V
BMP C126: Polyacrylanide for Soil Erosion V
Protection
BMP C130: Surface Roughening V V
BMPC131: Gradient Terraces V V
BMP C140: Dust Control V
BMP C150: Materials On Hand V V
BMP C151: Concrete Handling V
BMP C152: Sawcutting and Surfacing V
Pollution Prevention
BMP C153: Material Delivery,Storage and V
Containment
•
•
•
•
BMP C154: Concrete Washout Area V
BMP C160: Certified Erosion and V V
Sediment Control Lead
BMP C162:Scheduling V
Table 4.2.1 Runoff Conveyance and Treatment BMP's by SWPPP Element
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
Element 03 (3ntsrtt Element A6 Element IP Element t� EleneM%9 Element a10 Element fi13
BIAP or Element Name Control Iltshlll Protract Muted Stabilize Control Control De- Protect Low
Flow Rates Ssdkreent Slopes Drain inlets Channels Pollutants Wintering impact
Controls and Outsets 3evelop.nent
gNP C200: Interceptor Dike and Swale ✓ ✓
811.4P C201: Grass-Lined Chattels ✓
t3UP C202:Channel Lining ✓ --
SOAP C203: Water Bars ✓ ✓
I J
BMP C204: Pipe Slope Drams ✓
UMP C206: Subsurface Drains ✓ -- ——
BMP C206; Level Spreader ✓
11MP C207: Check Dams ✓ ✓
8MP C201: Triangular Mt Dike fOeolax111e ✓ - ✓
Encased Check Dett)
BMP C209: Outlet Protection ✓
r BMP C220; Storm Drain Inlet Protection ✓
BMP C231: Brush Barrier ✓ ✓
BMP C232: Gravel Filler Berm ✓
BMP C233: Sit Fence ,/ ✓
BMP C234: Vegetated Strip ✓ ✓
BMP C235: Wattles ✓
BMP C236:Vegittrtive Filtration ✓
BMP C240: Sediment Trap ✓ ✓
BMP C241: Temporary Sed neat Pond ✓ ✓
BMP C250: Construction Storm ter ✓
Chemical Treatnxnt
BMP C251:Construction Stormenter ✓
Filtration
BMP C252:High pH Neutralization Using
CO2
BMP C253:pH Control for High pH Water ✓
13 Elements of SWPPP
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
(Construction Stormwater Pollution Prevention Plan)
Please check off boxes to show that each element has been read and understood. Provide details where
applicable and if certain aspects are unnecessary or exempt, clearly justify. Details of the 13 Elements and the
correlating BMPs are listed Above from the 2014 Stormwater Management Manual for Western Washington
(SWMMWW). A link is provided on the City of Anacortes website, under Planning, Community, & Economic
Development Department, as well as under Stormwater on the Engineering Division of Public Work's page.
Owner Name: _Zach Mosner& Patricia Friedman
Site Address: _ 3708 Leeward Lane
Prepared By: _Jason Sterling
The Stormwater checklist or building permit determined that:
The 13 elements must be addressed * These elements must be addressed
for construction activity adding under for construction activity adding 2,000
2,000 sq. ft. of hard surface area. sq. ft. or more of hard surface area.
This means that an attached narrative
and site plan are required with this
document.
Under each element, provide the BMP's that will be applicable to your project. Use the attached Tables
provided.
ELEMENT 1: Preserve Vegetation/Mark Clearing Limits
❑ Before beginning land disturbing activities, including clearing and grading, clearly mark all clearing
limits, sensitive areas and their buffers, and trees that are to be preserved within the construction area.
Retain the duff layer, native top soil, and natural vegetation in an undisturbed state to the maximum
degree practical.
- A high visability construction fence will be installed at the North, West, and East lot boundary.
- This will be installed prior to beginning construction.
- BMP to be monitored daily and repaired as needed.
ELEMENT 2: Establish Construction Access
❑ Limit construction vehicle access and exit to one route, if possible.
❑ Stabilize access points with a pad of quarry spalls, crushed rock, or other equivalent BMPs, to minimize
tracking onto roads.
❑ Locate wheel wash or tire baths on site, if the stabilized construction entrance is not effective in
preventing tracking sediment onto roads.
❑ If sediment is tracked off site, clean the affected roadway thoroughly at the end of each day, or more
frequently as necessary (ex: wet weather). Remove sediment from roads by shoveling, sweeping, or
pick up and transport the sediment to a controlled sediment disposal area.
❑ Conduct street washing only after sediment is removed in accordance with the above bullet.
❑ Control street wash wastewater by pumping back on site or otherwise preventing it from discharging
into systems tributary to waters of the State.
- Per BMP C105 a Stabilized Construction Entrance will be installed. Vehicle traffic to the
construction site will be limited to one route.
- Any dirt or mud that is tracked onto the roadway will be clean immediately.
- To be installed prior to construction.
- BMP to be monitored daily and repaired as needed.
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
ELEMENT 3: Control Flow Rates
❑ Protect properties and waterways downstream of development sites from erosion and the associated
discharge of turbid waters due to increases in the velocity and peak volumetric flow rate of stormwater
runoff from the project site.
❑ Where necessary to comply with the bullet above, construct stormwater retention or detention facilities
as one of the first steps in grading. Assure that detention facilities function properly before constructing
site improvement (e.g. impervious surfaces).
❑ If permanent infiltration ponds are used for flow control during construction, protect these facilities from
siltation during the construction phase.
- Not applicable to this project. There are no storm-water swales or retention facilities to control.
ELEMENT 4: Install Sediment Controls
Design, install, and maintain effective erosion controls and sediment controls to minimize the discharge
of pollutants.
❑ Construct sediment control BMPs (sediment ponds, traps, filters, etc.) as one of the first steps in
grading. These BMPs shall be functional before other land disturbing activities take place.
❑ Minimize sediment discharges from the site. The design, installation and maintenance of erosion and
sediment controls must address factors such as the amount, frequency, intensity and duration of
precipitation, the nature of resulting stormwater runoff, and soil characteristics, including the range of
soil particle sizes expected to be present on the site.
❑ Direct stormwater runoff from disturbed areas through a sediment pond or other appropriate sediment
removal BMP, before the runoff leaves a construction site or before discharge to an infiltration facility.
Runoff from fully stabilized areas may be discharged without a sediment removal BMP, but must meet
the flow control performance standard in Element#3, bullet#1.
❑ Locate BMPs intended to trap sediment on-site in a manner to avoid interference with the movement of
juvenile salmonids attempting to enter off-channel areas or drainages.
❑ Provide and maintain natural buffers around surface waters, direct stormwater to vegetated areas to
increase sediment removal, and maximize stormwater infiltration.
❑ Where feasible, design outlet structures that withdraw impounded stormwater from the surface to avoid
discharging sediment that is still suspended lower in the water column.
- Per BMP C233 a silt fence will be installed on the lower section of the lot boundaries per the site
plan.
- To be installed prior to the start of construction.
- BMP to be monitored daily and repaired as needed.
ELEMENT 5: Stabilize Soils
❑ Stabilize exposed and unworked soils by application of effective BMPs that prevent erosion. Applicable
BMPs include, but are not limited to: temporary and permanent seeding, sodding, mulching, plastic
covering, erosion control fabrics and matting, soil application of polyacrylamide (PAM), the early
application of gravel base early on areas to be paved, and dust control.
❑ Control stormwater volume and velocity within the site to minimize soil erosion.
❑ Control stormwater discharges, including both peak flow rates and total stormwater volume, to minimize
erosion at outlets and to minimize downstream channel and stream bank erosion.
Soils must not remain exposed and unworked for more than the time periods set forth below to prevent
erosion.
o During the dry season (May 1 — Sept 30): 7 days
o During the wet season (Oct 1 —Apr 30): 2 days
Stabilize soils at the end of the shift before a holiday or weekend if needed based on the weather
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
forecast.
n Stabilize soil stockpiles from erosion, protect with sediment trapping measures, and where possible, be
located away from storm drain inlets, waterways, and drainage channels.
❑ Minimize the amount of soil exposed during construction activity.
❑ Minimize the disturbance of steep slopes.
n Minimize soil compaction and, unless infeasible, preserve topsoil.
- Stabilize exposed and unworked soils by application of effective BMPs that prevent erosion.
Applicable BMPs include, but are not limited to: temporary and permanent seeding, sodding,
mulching, plastic covering, erosion control fabrics and matting, soil application of polyacrylamide
(PAM), the early application of gravel base early on areas to be paved, and dust control. Install
plastic covering per BMP C123 on Soils Stockpiles. BMP to be monitored daily and repaired as
needed.
ELEMENT 6: Protect Slopes
❑ Design and construct cut-and-fill slopes in a manner to minimize erosion. Applicable practices include,
but are not limited to, reducing continuous length of slope with terracing and diversions, reducing slope
steepness, and roughening slope surfaces (Ex: track walking).
❑ Divert off-site stormwater (run-on) or ground water away from slopes and disturbed areas with
interceptor dikes, pipes, and/or swales. Off-site stormwater should be managed separately from
stormwater generated on the site.
At the top of slopes, collect drainage in pipe slop drains or protected channels to prevent erosion.
o *Temporary pipe slope drains must handle the peak volumetric flow rate calculated using a 10-
minute time step from a Type 1A, 10-year, 24-hour frequency storm for the developed condition.
Alternatively, the 10-year, 1-hour flow rate predicted/indicated by an approved continuous runoff
model, increased by a factor of 1.6, may be used. The hydrologic analysis must use the existing
land cover condition for predicting flow rates from tributary areas outside the project limits. For
tributary areas on the project site, the analysis must use the temporary or permanent project
land cover condition, whichever will produce the highest flow rates. If using the Western
Washington Hydrology Model (WWHM) to predict flows, bare soil areas should be modeled as
"landscaped" area.
o Where 15-minute time steps are available in an approved continuous runoff model, they may be
used directly without a correction factor.
❑ Place excavated material on the uphill side of trenches, consistent with safety and space
considerations.
❑ Place check dams at regular intervals within constructed channels that are cut down a slope.
❑ Consider soil types and its potential for erosion.
n Stabilize soils on slopes, as specified in Element 5.
n BMP combinations are the most effective method of protecting slopes with disturbed soils. Ex: Use both
mulching and straw erosion control blankets.
- Design and construct cut-and-fill slopes in a manner to minimize erosion. Applicable practices
include, but are not limited to, reducing continuous length of slope with terracing and diversions,
reducing slope steepness, and roughening slope surfaces (for example, track walking). To be
installed as soon as grading for home site is established and slopes are present at the site.
- BMP to be monitored daily and repaired as needed.
ELEMENT 7: Protect Drain Inlets
❑ Protect all storm drain inlets made operable during construction so that stormwater runoff does not
enter the conveyance system without first being filtered or treated to remove sediment.
❑ Clean or remove and replace inlet protection devices when sediment has filled one-third of the available
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
storage (unless a different standard is specified by the product manufacturer).
❑ Where possible, protect all existing storm drain inlets so that stormwater runoff does not enter the
conveyance system without first being filtered or treated to remove sediment.
Keep all approach roads clean. Do not allow sediment and street wash water to enter storm drains
without prior and adequate treatment unless treatment is provided before the storm drain discharges to
waters of the State.
Inlets should be inspected weekly at a minimum and daily during storm events.
- Per detail 1-40.20-00 Storm Drain Inlet protection devices will be installed at existing catch basins in
the immediate vicinity of the project.
- To be installed prior to the start of any construction.
- BMP to be monitored daily and repaired as needed.
ELEMENT 8: Stabilize Channels and Outlets
❑ Design, construct, and stabilize all on-site conveyance channels to prevent erosion from the following
expected peak flows:
o *Channels must handle same peak volumetric flow rate as temporary pipe slope drains listed in
Element 6, above.
❑ Provide stabilization, including armoring material, adequate to prevent erosion of outlets, adjacent
streambanks, slopes, and downstream reaches at the outlets of all conveyance systems.
The best method for stabilizing channels is to completely line the channel with a blanket product first,
then add check dams as necessary to function as an anchor and to slow the flow of water.
- No stormwater runoff will be conveyed off site via channels, swales, or streams.
ELEMENT 9: Control Pollutants
Design, install, implement, and maintain effective pollution prevention measures to minimize the
discharge of pollutants.
❑ Handle and dispose of all pollutants, including waste materials and demolition debris that occur on-site
in a manner that does not cause contamination of stormwater.
Provide cover, containment, and protection from vandalism for all chemicals, liquid products, petroleum
products, and other materials that have the potential to pose a threat to human health or the
environment. On-site fueling tanks must include secondary containment. Secondary containment
means placing tanks or containers within an impervious structure capable of containing 110% of the
volume contained in the largest tank within the containment structure. Double-walled tanks do not
require additional secondary containment.
❑ Conduct maintenance, fueling, and repair of heavy equipment and vehicles using spill prevention and
control measures. Clean contaminated surfaces immediately following any spill incident.
❑ Discharge wheel wash or tire bath wastewater to a separate on-site treatment system that prevents
discharge to surface water, such as closed-loop recirculation or upland land application, or to the
sanitary sewer, with local sewer district approval. Wheel wash or tire bath wastewater should not
include wastewater from concrete washout areas.
❑ Apply fertilizers and pesticides in a manner and at application rates that will not result in loss of
chemical to stormwater runoff. Follow manufacturers' label requirements for application rates and
procedures.
Use BMPs to prevent contamination of stormwater runoff by pH-modifying sources. The sources for this
contamination include, but are not limited to: bulk cement, cement kiln dust, fly ash, new concrete
washing and curing waters, waste streams generated from concrete grinding and sawing, exposed
aggregate processes, dewatering concrete vaults, concrete pumping, and mixer washout waters. Adjust
the pH of stormwater if necessary to prevent violations of the water quality standards.
❑ Assure that washout of concrete trucks is performed off-site or in designated concrete washout areas
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
only. Do not wash out concrete trucks onto the ground, or into storm drains, open ditches, streets, or
streams. Do not dump excess concrete on site, except in designated concrete washout areas. Concrete
spillage or concrete discharge to surface waters of the State is prohibited. Do not use upland land
applications for discharging wastewater from concrete washout areas.
❑ Obtain written approval from Ecology and provide to the City before using chemical treatment other
than CO2 or dry ice to adjust pH.
❑ Woody debris may be chopped and spread on site.
❑ Conduct oil changes, hydraulic system drain down, solvent and de-greasing cleaning operations, fuel
tank drain down and removal, and other activities which may result in discharge or spillage of pollutants
to the ground or into stormwater runoff using spill prevention measures, such as drip pans.
❑ Clean contaminated surfaces immediately following any discharge or spill incident. Emergency repairs
may be performed on-site using temporary plastic placed beneath and, if raining, over the vehicle.
- Per BMP C154 a Concrete Washout Area is to be installed onsite to capture contaminated water
from concrete washouts.
- To be installed prior to foundation / concrete installation.
- BMP to be monitored daily and repaired as needed.
ELEMENT 10: Control De-Watering
❑ Discharge foundation, vault, and trench dewatering water, which have characteristics similar to
stormwater runoff at the site, into a controlled conveyance system before discharge to a sediment trap
or sediment pond.
❑ Discharge clean, non-turbid de-watering water, such as well-point ground water, to systems tributary to,
or directly into surface waters of the State, as specified in Element 8, provided the de-watering flow
does not cause erosion or flooding of receiving waters or interfere with the operation of the system. Do
not route clean dewatering water through stormwater sediment ponds. Note that "surface waters of the
State" may exist on a construction site as well as off site; for example, a creek running through a site.
❑ Handle highly turbid or contaminated dewatering water separately from stormwater.
❑ Other treatment or disposal options may include:
1. Infiltration
2. Transport off-site in a vehicle, such as a vacuum flush truck, for legal disposal in a manner that
does not pollute state waters.
3. Ecology-approved on-site chemical treatment or other suitable treatment technologies.
4. Sanitary or combined sewer discharge with local sewer district approval, if there is no other
option.
5. Use of a sedimentation bag with outfall to a ditch or swale for small volumes of localized
dewatering.
Construction equipment operation, clamshell digging, concrete tremie pour, or work inside a cofferdam
can create highly turbid or contaminated dewatering water.
❑ Discharging sediment-laden (muddy) water into waters of the State likely constitutes a violation of water
quality standards for turbidity. The easiest way to avoid discharging muddy water is through infiltration
and preserving vegetation.
- No dewatering will occur during the construction of this site.
ELEMENT 11: Maintain BMPs
❑ Maintain and repair all temporary and permanent erosion and sediment control BMPs as needed to
assure continued performance of their intended function in accordance with BMP specifications.
Remove all temporary erosion and sediment control BMPs within 30 days after achieving final site
stabilization or after the temporary BMPs are no longer needed. Some temporary erosion and sediment
control BMPs are bio-degradable and designed to remain in place following construction such as
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
compost socks.
❑ Provide protection to all BMPs installed for the permanent control of stormwater from sediment and
compaction. All BMPs that are to remain in place following completion of construction shall be
examined and placed in full operating conditions. If sediment enters the BMPs during construction, it
shall be removed and the facility shall be returned to the conditions specified in the construction
documents.
Remove or stabilize trapped sediment on site. Permanently stabilize disturbed soil resulting from
removal of BMPs or vegetation.
- BMP to be monitored daily and repaired as needed.
ELEMENT 12: Manage the Project— Projects subject to Minimum Requirements 1-9 must have a Certified
Erosion and Sediment Control Lead (CESCL)for site inspections. Projects subject to Minimum Requirements
1-5 do not require the inspector to be certified. By the initiation of construction, the SWPPP must identify the
CESCL or inspector, who shall be present on-site or on-call at all times.
❑ Phase development projects to the maximum degree practicable and take into account seasonal work
limits to prevent soil erosion and prevent transporting sediment from the site during construction.
❑ Inspection and monitoring — Inspect, maintain, and repair all BMPs as needed to assure continued
performance of their intended function.
❑ Maintain, update, and implement the SWPPP.
❑ Clearing and grading activities for developments shall be permitted only if conducted using an approved
site development plan (e.g., subdivision approval).
❑ From Oct 1 through Apr 30, clearing, grading, and other soil disturbing activities is permitted only if
shown that the site operator will prevent silt-laden runoff from leaving the site through a combination of
the following:
1. Site conditions including existing vegetative coverage, slope, soil type, and proximity to
receiving waters.
2. Limit activities and the extent of disturbed areas.
3. Proposed erosion and sediment control measures.
Weather conditions can influence the seasonal limitation on site disturbance. The City of Anacortes has
the authority to take enforcement action per AMC 19.76 Stormwater.
❑ The following activities are exempt from the seasonal clearing and grading limitations:
1. Routine maintenance and necessary repair of erosion and sediment control BMPs;
2. Routine maintenance of public facilities or existing utility structures that do not expose the soil or
result in the removal of the vegetative cover to soil
3. Activities where there is 100% infiltration of surface water runoff within the site in approved and
installed erosion and sediment control facilities.
- BMP to be monitored daily and repaired as needed.
ELEMENT 13: Protect Low Impact Development BMPS
❑ If implementing any bioretention facilities or rain gardens, refer to the applicable BMP sections of the
Manual for requirements.
- N/A
01/05/2021
Applicant Signature Date
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
APPENDIX 1 —Survey performed by a Professional Land Surveyor
The object of this appendix is to ensure that the property has a minimum of 3 out of 5 property corners
visible to ensure that the structures are placed within the required setbacks.
- Submitted with permit pack
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
APPENDIX 2 —Soils Anaylsis (Volume 1, Chapter 3.1.1)
- See submitted GeoTest report
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
APPENDIX 3 — Model Soil Management Plan for BMP T5.13
An alternate document acceptable to the City of Anacortes is a Test Report provided by the Soils Supplier that
identifies the soils to be used meet the specifications outlined under Minimum Requirement 5. The
specifications are in both WSDOT and CSI Formats. For specifications, refer to the above referenced PDF.
This submittal can be a deferred submittal since most projects are not sure who the supplier will be at the time
of building permit application. For projects that trigger Minimum Requirements 1 through 5, the Test Report will
be provided to the Building Department. Projects triggering Minimum Requirements 1 through 9, the Test
Report will be provided to the Engineering Department.
- BMP T5.13 to be a deffered submittal, to be completed at final grading
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
DEFERRED SUBMITTAL: PROVIDE A TEST REPORT FROM SOILS SUPPLIER TO THE BUILDING DEPT.
PROJECT INFORMATION "Model Soil Management Plan for BMP T5.13" age# of pages
Complete all information on page 1;only site address and permit number on additional pages.
Site Address/Lot No.:
Permit Type: Permit Number:
Permit Holder: Phone:
Mailing Address:
Contact Person: Phone:
Plan Prepared By:
ATTACHMENTS REQUIRED (Check off required items that are attached to this plan)
Site Plan showing,to scale: Areas of undisturbed native vegetation(no amendment required)
New planting beds and turf areas(amendment required)
Type of soil improvement proposed for each area
Soil test results(required if proposing custom amendment rates)
Product test results for proposed amendments
AREA# (should match Area#on Site Plan)
PLANTING TYPE Turf Undisturbed native vegetation
Planting Beds Other:
SQUARE FOOTAGE OF THIS AREA: square feet
SCARIFICATION inches(depth)of scarification needed to achieve finished total 12"loosened depth.
Subsoil will be scarified
PRE-APPROVED inches of compost or imported topsoil applied
AMENDMENT METHOD: X 3.1 (conversion factor, inches to cubic yards) PRODUCT:
Topsoil import =cu.yards per 1,000 sq. ft.
Amend with compost X ,000s sq.ft. in this area
Stockpile and amend =cubic yards of amendment —*—>—*—>— QUANTITY: CU.YDS.
( cu.yds. stockpiled) (needed to cover this area to designated depth)
CUSTOM AMENDMENT Attach test results and calculations.
Topsoil import inches organic matter or topsoil import PRODUCT:
Topsoil&compost lift X 3.1
Amend =cu.yards/ 1,000 sq. ft.
Stockpile and amend X ,000s sq.ft. in this area
( cu.yds.stockpiled) =cubic yards of amendment ——*—*—— QUANTITY: CU.YDS.
MULCH ,000 sq.ft. PRODUCT:
X 6.2 (conversion, to give 2 inch mulch depth)
=cubic yards of mulch —*—*—*—*—*—> QUANTITY: CU.YDS.
TOTAL AMENDMENT/TOPSOIL/MULCH FOR ALL AREAS (complete on page 1 only, totaling all areas/pages in this Plan)
❑ Product#1: ❑ Quantity: cu.yds.
❑ Test Results: %organic matter C:N ratio<25:1 (except mulch,or<35:1 for native plants) "stable"(yes/no)
❑ Product#2: ❑ Quantity: cu.yds.
❑ Test Results: %organic matter C:N ratio<25:1 (except mulch,or<35:1 for native plants) "stable"(yes/no)
❑ Product#3: ❑ Quantity: cu.yds.
❑ Test Results: %organic matter C:N ratio<25:1 (except mulch,or<35:1 for native plants) "stable"(yes/no)
Date: Inspector: Approved: Revisions Required:
Date: Inspector: Approved: Revisions Required:
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
APPENDIX 4 — Determining Construction Site Sediment Damage Potential (Appendix 7— NPDES Phase
II Permit)
Note: See attached. All projects within the City of Anacortes are required to complete that document under
Appendix 4.
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
Western Washington Phase II Stormwater Permit
APPENDIX 7 - Determining Construction Site
Sediment Damage Potential
The following rating system allows objective evaluation of a particular development site's potential to
discharge sediment. Permittees may use the rating system below or develop alternative process
designed to identify site-specific features which indicate that the site must be inspected prior to clearing
and construction. Any alternative evaluation process must be documented and provide for equivalent
environmental review.
Step one is to determine if there is a sediment/erosion sensitive feature downstream of the development
site. If there is such a site downstream complete step two, assessment of hydraulic nearness. If there is
a sediment/erosion sensitive feature and it is hydraulically near the site then go to step three to
determine the construction site sediment transport potential.
ii. STEP 1 — Sediment/Erosion Sensitive Feature Identification
Sediment/erosion sensitive features are areas subject to significant degradation due to the effect of
sediment deposition or erosion. Special protection must be provided to protect them.
Sediment/erosion sensitive features include but are not limited to:
i. Salmonid bearing fresh water streams and their tributaries or freshwater streams that
would be Salmonid bearing if not for anthropogenic barriers;
ii. Lakes;
iii. Category I, II, and III wetlands;
iv. Marine near-shore habitat;
v. Sites containing contaminated soils where erosion could cause dispersal of
contaminants; and
vi. Steep slopes (25% or greater) associated with one of the above features.
Identify any sediment/erosion sensitive features, and proceed to step two. If there are none the assessment
is complete.
iii. STEP 2 — Hydraulic Nearness Assessment
Sites are hydraulically near a feature if the pollutant load and peak quantity of runoff from the site will not
be naturally attenuated before entering the feature. The conditions that render a site hydraulically near
to a feature include, but are not limited to, the following:
i. The feature or a buffer to protect the feature is within 200 feet downstream of the site.
ii. Runoff from the site is tight-lined to the feature or flows to the feature through a channel
or ditch.
August 1, 2013, Modified January 16, 2015 Appendix 7- Determining Sediment Damage
Version Date: October 7, 2019 Previous Version Date: February 20, 2019
A site is not hydraulically near a feature if one of the following takes place to provide attenuation
before runoff from the site enters the feature:
iv. Sheet flow through a vegetated area with dense ground cover
v. Flow through a wetland not included as a sensitive feature
vi. Flow through a significant shallow or adverse slope, not in a conveyance
channel, between the site and the sensitive feature.
Identify any of the sediment/erosion sensitive features from step one that are hydraulically near
the site, and proceed to step three. If none of the sediment/erosion sensitive features are
hydraulically near the site, the assessment is complete.
vii. STEP 3 — Construction Site Sediment Transport Potential
Using the worksheet below, determine the total points for each development site. Assign points
based on the most critical condition that affects 10% or more of the site.
If soil testing has been performed on site, the results should be used to determine the
predominant soil type on the site. Otherwise, soil information should be obtained from the
county soil survey to determine Hydrologic Soil Group (Table of Engineering Index Properties
for step 1.D) and Erosion Potential (Table of Water Features for step 1.E)
When using the county soil survey, the dominant soil type may be in question, particularly when
the site falls on a boundary between two soil types or when one of two soil types may be present
on a site. In this case, the soil type resulting in the most points on the rating system will be
assumed unless site soil tests indicate that another soil type dominates the site.
Use the point score from Step 3 to determine whether the development site has a high potential
for sediment transport off of the site.
Total Score Transport Rating
<100 Low
1 100 High
A high transport rating indicates a higher risk that the site will generate sediment contaminated
runoff.
Construction Site Sediment Transport Potential Worksheet
A. Existing slope of site (average, weighted by aerial extent): Points
2% or less ...0
>2-5% 5
>5-10% 15
>10-15% 30
>15% 50
B. Site Area to be cleared and/or graded:
<5,000 sq. ft 0
5,000 sq. ft. — 1 acre 30
>1 acres 50
C. Quantity of cut and/or fill on site:
<500 cubic yards 0
500 — 5,000 cubic yards 5
>5,000 — 10,000 cubic yards 10
>10,000 —20,000 cubic yards 25
>20,000 cubic yards 40
D. Runoff potential of predominant soils (Natural Resources Conservation Service):
Hydrologic soil group A 0
Hydrologic soil group B 10
Hydrologic soil group C 20
Hydrologic soil group D 40
E. Erosion Potential of predominant soils (Unified Classification System):
GW, GP, SW, SP soils 0
Dual classifications (GW-GM, GP-GM, GW-GC,
GP-GC, SW-SM, SW-SC, SP-SM, SP-SC) 10
GM, GC, SM, SC soils 20
ML, CL, MH, CH soils 40
F. Surface or Groundwater entering site identified and intercepted 1:
Yes 0
No 25
G. Depth of cut or height of fill >10 feet:
Yes 25
No 0
H. Clearing and grading will occur in the wet season (October 1 — May 1):
Yes 50
No 0
TOTAL POINTS > 100 225
1 If no surface or groundwater enters site, give 0 points.
APPENDIX 5—Site Plan with all applicable information (Minimum Size 11x17 at a legible scale)
- Site plan submitted electronically with permit pack
APPENDIX 6 — Documented Site Photos (Show all directions of the site, including frontage)
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Location: South side of lot near road.
Description of the photo: South side of lot near road looking towards the north side of lot.
Photo taken by: Jason Sterling
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Location: South-East side of lot near road.
Description of the photo: South-east side of lot near road looking at frontage of lot.
Photo taken by: Jason Sterling
APPENDIX 7 — Drainage BMP Facility Maintenance Covenant
Note: To be recorded prior to: 1) Temporary Certificate of Occupancy; 2) Final Certificate of Occupancy, and
or; 3) Final Acceptance of the project.
This is Covenant is required for any Permanent Stormwater Facility constructed on a project site. The applicant
should work with the the City of Anacortes Engineering Department on formalizing the document for recording.
- To be deffered submittal
GVI o PLANNING, COMMUNITY, &ECONOMIC DEVELOPMENT DEPARTMENT
PLAN REVISION /ADDITIONAL INFORMATION COVER SHEET
Mailing Address:P.O. Box 547, Anacortes, WA 98221Office Location: 904 6th Street, Anacortes WA 98821
Phone: (360) 299-1984, Fax: (360) 293-1938
Please use this form to submit revisions or additional information to your permit application.
Permit/Project#: 3708 Leeward Lane Date: 02/21/2021
Project Name: MOSNER-FRIEDMAN RESIDENCE Project Address: 3708 Leeward Lane
Project Contact: Jason Sterling Company Name: Strandberg Construction Inc.
Contact Phone: 360.293.7431 Contact Email: jasons@strandbergconstruction.com
Has the permit been issued yet? ❑ Yes ■ No
All revisions must be either clouded or highlighted &wet stamped by an architect/engineer(if applicable).
Has this been done? ■ Yes ❑ No
Is the plan revision or additional information,in response to a plan review letter?
O Yes. A copy of the plan review letter with itemized responses to each item is required.
O No, the revision or additional information is initiated by the applicant, designer,or builder.
If not in response to a Plan Review Letter, please explain the nature of the revisions and/or additional
information:
Are you submitting a full replacement O Yes ® No
If not,what page#or title is being replaced:
Two full sized copies of all revised/additional information is required. Has this been done? N Yes ❑ No
Check the box next to the type of plan, report, or calculation where revisions or additional information
can be found.
O Site Plan 0 Building Plans ❑ Structural Plan
❑ Landscape Plan ❑ Parking Plan ❑ Tree Preservation Plan
❑ Arborist Report ❑ SEPA checklist ❑ Wetland Report
❑ Geotechnical Report ❑ Storm Drainage Analysis 0 TESC Plan
❑ Civil Plan ❑ Lot Coverage Calculations ❑ Impervious Surface Calculations
❑ FAR Calculations 0 Grading Plan 0 Survey(Boundary/Topographic)
O Mechanical Plan 0 Plumbing Plan 0 Other: