HomeMy WebLinkAboutM_ERC_MitMeasAdvisNotes_180824.pdfDEPARTMENT OF COMMUNITY
AND ECONOMIC DEVELOPMENT
SIGNATURES:
Gregg Zimmerman, Administrator
Public Works Department
Date Rick M. Marshall, Administrator
Renton Regional Fire Authority
Date
Kelly Beymer, Administrator
Community Services Department
Date C.E. Vincent, Administrator Date
Department Of Community & Economic Development
ENVIRONMENTAL (SEPA) DETERMINATION OF
NON-SIGNIFICANCE - MITIGATED (DNS-M)
PROJECT NUMBER: LUA17-000189
APPLICANT: Jamie Waltier, Harbour Homes, LLC / jwaltier@harbourhomes.com / 1441 N
34th St, Ste 300, Seattle, WA 98103
PROJECT NAME: Cedars at the Highlands
PROJECT DESCRIPTION: The applicant is requesting Preliminary Plat, SEPA Environmental Review, and a
Tier II Temporary Use Permit for approval of a 14-lot subdivision. The 4.49 acre site is located at 14120 160th Ave SE (APN
1457500110) within the Residential-4 zoning district. The rectangular shaped parcel would be divided into 14 residential
lots, a storm drainage tract, a tree retention tract, and a critical area tract. The 8,361 square feet (sf) drainage tract consists
of a stormwater vault located at the southeast corner of the site. The applicant would dedicate 28,777 sf for public right-
of-way to serve the new lots. The proposed lots would range in size from 9,002 sf to 16,100 sf with an average lot size of
10,224 sf. The plat would result in a net density of 3.66 du/ac. Access to the site would be gained by extending a residential
access road (Road A) from 160th Ave SE through the center of the lot. The site contains a Type Ns Stream in the northeast
corner of the site that requires a minimum 50 ft buffer as well as a 15 ft building setback. No areas meeting wetland
criteria were found on the site. Soils consist of medium dense to dense silty sand with gravel and stiff silt (ML). The soil
density was observed to increase with depth. The west side of the site is relatively flat. However, the east side of the site
descends approximately ten feet towards the southeastern property line. The existing shop and barn are proposed to
remain as part of the plat construction. There are 284 significant trees on the site and the applicant is proposing to retain
41 original trees. The applicant has submitted an Arborist Report, Critical Areas Study, Technical Information Report,
Traffic Impact Analysis, and a Geotechnical Engineering Study with the application.
PROJECT LOCATION: 14120 160th Ave SE, Renton WA 98059
LEAD AGENCY: City of Renton
Environmental Review Committee
Department of Community & Economic Development
The City of Renton Environmental Review Committee has determined that it does not have a probable significant adverse
impact on the environment. An Environmental Impact Statement (EIS) is not required under RCW 43.21C.030(2)(c).
Conditions were imposed as mitigation measures by the Environmental Review Committee under their authority of
Section 4-9-070D Renton Municipal Code. These conditions are necessary to mitigate environmental impacts identified
during the environmental review process. Because other agencies of jurisdiction may be involved, the lead agency will not
act on this proposal for fourteen (14) days.
Appeals of the environmental determination must be filed in writing on or before 5:00 p.m. on September 7, 2018.
Appeals must be filed in writing together with the required fee with: Hearing Examiner, City of Renton, 1055 South Grady
Way, Renton, WA 98057. Appeals to the Examiner are governed by RMC 4-8-110 and more information may be obtained
from the Renton City Clerk’s Office, (425) 430-6510.
PUBLICATION DATE: August 24, 2018
DATE OF DECISION: August 20, 2018
DocuSign Envelope ID: DA5EE113-EBEA-486A-A176-507A6F80B5DC
8/21/2018 | 3:24 PM PDT
8/20/2018 | 2:13 PM PDT
8/20/2018 | 3:43 PM PDT
8/20/2018 | 3:47 PM PDT
DETERMINATION OF NON-SIGNIFICANCE – MITIGATED
(DNS-M) MITIGATION MEASURES AND ADVISORY NOTES
PROJECT NUMBER: LUA17-000189, ECF, PP, TU
APPLICANT: Jamie Waltier, Harbour Homes, LLC / 1441 N 34th St, Ste 300,
Seattle, WA 98103 / jwaltier@harbourhomes.com / 206-315-8130
PROJECT NAME: Cedars at the Highlands
PROJECT DESCRIPTION: The applicant is requesting Preliminary Plat approval and
Environmental Threshold Determination (SEPA) for a proposed 13-lot subdivision. The project site is
195,531 square feet (4.49 acres) and is located at 14120 160th Ave SE. The project site is located in the
Residential-4 (R-4) zoning designation. The proposed single-family residential lots range in size from
9,000 square feet to 17,565 square feet with an overall proposed density of 3.36 dwellings per acre. The
applicant has requested a Temporary Use Permit to allow for two existing outbuildings to remain for a
period of five years. The structures are located across proposed Lots 9 and 10. Additional proposed
improvements include a 3,195 sq. ft. storm drainage tract (Tract A) in the southeast corner of the site
along the unimproved 162nd Ave SE right-of-way (ROW) frontage, a 3,500 sq. ft. tree retention tract
(Tract C) along the north property line adjacent to lots 11 and 12, and a 20,246 native growth protection
tract (Tract B) in the north-east corner to encompass the proposed 75-foot reduced wetland buffer. The
proposed lots would be served by a new public residential access street off of 160th Ave SE and a cul-de-
sac would be provided near the eastern end of the property. Proposed lots would be served by sanitary
sewer along the new street that would connect to an existing main within 160th Ave SE. Proposed lots
would be served by a new water main extending from 160th Ave SE along the new street. Construction
of the proposed subdivision infrastructure improvements would result in approximately 5,000 cubic
yards of cut and 8,000 cubic yards of fill. A Type Ns stream and Category III wetlands are mapped on the
site according to COR maps and a Wetlands Report submitted by the applicant . Slopes on the site
generally fall to the southeast across the property at a range of 0-20%. Soils consist of Alderwood
gravelly sandy loam (AgC). The applicant has proposed to retain approximately 35 of the 284 significant
trees onsite. The applicant has submitted a Technical Information Report, Arborist Report, a Critical
Areas Determination and a Geotechnical Engineering Study with the application.
PROJECT LOCATION: 14120 160th Ave SE, Renton WA 98059
LEAD AGENCY: The City of Renton
Department of Community & Economic Development
Planning Division
MITIGATION MEASURES:
1. Project construction shall comply with the recommendations found in the submitted geotechnical
support prepared by Earthworks NW, dated February 23, 2017.
ADIVISORY NOTES:
The following notes are supplemental information provided in conjunction with the administrative
land use action. Because these notes are provided as information only, they are not subject to the
appeal process for the land use actions.
DEPARTMENT OF COMMUNITY
AND ECONOMIC DEVELOPMENT
Page 1 of 6 LUA**-000***
ADVISORY NOTES TO APPLICANT
The following notes are supplemental information provided in conjunction with the administrative land use
action. Because these notes are provided as information only, they are not subject to the appeal process for
the land use action.
Planning:
(Contact: Name, 425-430-7219, amorganroth@rentonwa.gov)
1. RMC section 4-4-030.C.2 limits haul hours between 8:30 am to 3:30 pm, Monday through Friday unless
otherwise approved by the Development Services Division.
2. Commercial, multi-family, new single family and other nonresidential construction activities shall be
restricted to the hours between seven o’clock (7:00) a.m. and eight o’clock (8:00) p.m., Monday through
Friday. Work on Saturdays shall be restricted to the hours between nine o’clock (9:00) a.m. and eight
o’clock (8:00) p.m. No work shall be permitted on Sundays.
3. Within thirty (30) days of completion of grading work, the applicant shall hydroseed or plant an
appropriate ground cover over any portion of the site that is graded or cleared of vegetation and where
no further construction work will occur within ninety (90) days. Alternative measures such as mulch,
sodding, or plastic covering as specified in the current King County Surface Water Management Design
Manual as adopted by the City of Renton may be proposed bet ween the dates of November 1st and
March 31st of each year. The Development Services Division’s approval of this work is required prior to
final inspection and approval of the permit.
4. A National Permit Discharge Elimination System (NPDES) permit is required when more than one acre is
being cleared.
5. The applicant will be required to submit a Final Wetlands Mitigation Report and Maintenance and
Monitoring proposal. In addition, the applicant will be required to comply with all the code requirements
of RMC 4-3-050 Critical Areas. This includes, but is not limited to, placing the critical area within a Native
Growth Protection Easement, providing fencing and signage, and providing the City with a site
restoration surety device and, later, a maintenance and moni toring surety device.
6. The applicant may not fill, excavate, stack or store any equipment, dispose of any materials, supplies or
fluids, operate any equipment, install impervious surfaces, or compact the earth in any way within the
area defined by the drip line of any tree to be retained.
7. The applicant shall erect and maintain six foot (6') high chain link temporary construction fencing around
the drip lines of all retained trees, or along the perimeter of a stand of retained trees. Placards shall be
placed on fencing every fifty feet (50') indicating the words, “NO TRESPASSING – Protected Trees” or on
each side of the fencing if less than fifty feet (50'). Site access to individually protected trees or groups
of trees shall be fenced and signed. Individual trees shall be fenced on four (4) sides. In addition, the
applicant shall provide supervision whenever equipment or trucks are moving near trees.
8. This permit is shall comply with the Bald and Golden Eagle Protection Act. The permitted is responsible
for adhering to the U.S. Fish and Wildlife Service National Bald Eagle Management Guidelines (2007) and
/or your U.S. Fish and Wildlife Service permit.
Development Engineering:
(Contact: Name, 425-430-7298, rnair@rentonwa.gov)
1. See Attached Development Engineering Memo dated August 17, 2017
ADVISORY NOTES TO APPLICANT
Page 2 of 6 LUA**-000***
Fire Authority:
(Contact: Corey Thomas, 425-430-7024, cthomas@rentonwa.gov)
Environmental Impact Comments:
1. The fire impact fees are applicable at the rate of $718.56 per single family unit. This fee is paid at
building permit issuance.
Code Related Comments:
1. The fire flow requirement for a single family home is 1,000 gpm minimum for dwellings up to 3,600
square feet (including garage and basements). If the dwelling exceeds 3,600 square feet, a minimum of
1,500 gpm fire flow would be required. A minimum of one fire hydrant is required within 300 -feet of the
proposed buildings and two hydrants if the fire flow goes up to 1,500 gpm. Ther e are no existing hydrants
within 300-feet of the proposed homes. Existing 4-inch water main in 160th Ave SE will not provide the
minimum required fire flow, new on-site and off-site water mains will be required. A water availability
certificate is required from King County Water District 90. Fire sprinkler systems may be required if
insufficient fire flow cannot be obtained.
2. Fire department apparatus access roadways are required to be a minim um of 20-feet wide fully paved,
with 25-feet inside and 45-feet outside turning radius. Fire access roadways shall be constructed to
support a 30-ton vehicle with 75-psi point loading. Access is required within 150-feet of all points on the
buildings. An approved cul-de-sac type 90-foot diameter turnaround is required for all dead end streets
exceeding 300-feet in length.
Building:
(Contact: Craig Burnell, 425-430-7290, cburnell@rentonwa.gov)
1. Recommendations of the geotechnical report must be followed as a condition of building permits.
ADVISORY NOTES TO APPLICANT
Page 3 of 6 LUA**-000***
DEPARTMENT OF COMMUNITY
AND ECONOMIC DEVELOPMENT
M E M O R A N D U M
DATE: August 17, 2017
TO: Alex Morganroth, Associate Planner
FROM: Rohini Nair, Civil Engineer III, Plan Review
SUBJECT: Cedars at the Highlands Plat
14120 160th Ave SE
LUA17-000189
I have reviewed the preliminary plat application for the above-referenced proposal located at parcel 1457500110 and
have the following comments:
EXISTING CONDITIONS
The site is approximately 4.49 acres in size and is rectangular in shape. The existing site is developed with an existing
workshop, one shed and gravel driveway. The site includes:
Water Water service is provided by King County Water District 90 (425-255-9600 or www.kcwd90.com). The site is
located outside of an Aquifer Protection Area.
Sewer Wastewater service is provided by the City of Renton. There is an existing 10-inch wastewater main located in
160th Ave SE (see City plan no. S-3235). There is an existing 8-inch wastewater main located in 162nd Ave SE
(see City plan no. S-3613).
Storm There is an existing 12-inch stormwater main located in 160th Ave SE. There is an existing stormwater ditch
located in 160th Ave SE fronting the subject property.
Streets The proposed development fronts 160th Ave SE along the west property line(s). 160th Ave SE is classified as a
Residential Access Road. Existing right-of-way (ROW) width is approximately 60 feet. The proposed
development fronts 162nd Ave SE along the east property line(s). 162nd Ave SE is classified as a Residential Access
Road, and is an unimproved right-of-way. Existing right-of-way (ROW) width is approximately 60 feet.
CODE REQUIREMENTS
WATER
1. A water availability certificate from King County Water District 90 was provided with the site plan submittal. The
water availability certificate noted that a flow rate of 1,500 gallons per minute (gpm) can be provided to the site
by an 8” water main extension to the site.
2. Review of the water plans will be conducted by King County Water District 90 and the Renton Regional Fire
Authority.
ADVISORY NOTES TO APPLICANT
Page 4 of 6 LUA**-000***
3. Plans approved by King County Water District 90 shall be routed to the City for final review prior to permit
issuance.
SEWER
1. The development is subject to a wastewater system development charge (SDC) fee. The 2018 SDC fee for sewer
is based on the size of the new domestic water to serve the project. The current sewer fee for a 1 -inch meter
install is $2,837.00 per meter. Each lot shall have a separate meter. The final fee amount is calculated and payable
at the time of construction permit issuance.
2. The development is in the Central Plateau Interceptor Special Assessment Districts (SADs).
a. The Area SAD fee for the Central Plateau Interceptor SAD is $351.95, plus interest of $0.05111 per day,
for each lot. As of 8/7/2018, the total SAD fee is calculated as $519.78 per lot. The final fee amount is
calculated and payable at the time of construction permit issuance.
b. The Frontage SAD fee for the Central Plateau Interceptor SAD is $5,810.34, plus interest of $0.84369 per
day, for each lot with frontage along 160th Ave SE. As of 8/7/2018, the total SAD fee is calculated as
$8,581.03 for each lot that has frontage on 160th Ave SE. The final fee amount is calculated and payable
at the time of construction permit issuance.
3. The existing sewer main along 160th Avenue SE along with the existing sewer service located on Lot 1 as shown on
the composite utility civil plan submitted with the Land Use Application.
4. The proposed sewer main improvements as shown on the composite utility civil plan submitted with the Land Use
Application provides the required 8-inch sewer main extension from the existing sewer main located in 162nd
Avenue SE and extending west into Cedars at the Highlands for future extension by the City. The required
extension of the new 8-inch sewer main from 162nd Avenue SE into the future public ROW is shown on the
conceptual utilities plan and provides the required sanitary sewer service to lots accessing off of internal project
street except Lot 1 which will utilize the existing sewer service on the lot. The lots accessing from 160th Avenue
SE will obtain sanitary sewer service from the existing 8-inch sewer main within 160th Avenue SE.
a. A 15-foot public sewer easement is shown A 15-foot public sewer easement shall be provided for the
extension of the sewer main through the stormwater tract for any portion of the extension located outside
of the public ROW.
5. All new side sewers shall be 6”. All side sewers shall flow by gravity to the main at a minimum slope of 2%. As
shown on the preliminary utility plan, each lot shall have its own side sewer.
SURFACE WATER
1. The development is subject to a storm water system development charge (SDC) fee. The 2018 SDC fee for storm
water is $1,718.00 for each new lot. The final fee amount is calculated and payable at the time of construction
permit issuance.
2. A Preliminary Drainage Plan and Technical Information Report (TIR) prepared by DR Strong dated June 29, 2018
were submitted to the City as part of the site plan submittal. The site is located in the City’s Flow Control Duration
Standard (Forested Site Conditions). The site is located in the Lower Cedar River drainage basin. The TIR was
completed in accordance with the standards found in the 2017 Renton Surface Water Design Manual (RSWDM).
All nine core and six special requirements were addressed.
A detention vault is proposed to meet the flow control facility requirement to satisfy Core Requirement #3. The
detention vault has been sized to the City’s Flood Problem Flow Control Standard (King County Level 3) using
WWHM to help mitigate potential downstream drainage issues. The project matches the pre-developed discharge
rates from 50% of the 2-year peak flow up to the full 50-year peak flow and peak discharge rates for the 2 and 10-
year return periods as required in the City’s Flow Control Duration Standard (Forested Site Conditions) area. In
addition, the site matches the 100-year peak discharge rate to the pre-developed 100-year peak discharge rate to
meet the City’s Flood Problem Flow Control Standard.
The project is subject to Basic Water Quality treatment standards to satisfy Core Requirement #8. A stormwater
quality vault following the detention vault will be utilized to address this requirement.
ADVISORY NOTES TO APPLICANT
Page 5 of 6 LUA**-000***
The project is subject to on-site BMP requirements found in Core Requirement #9. Full dispersion and full
infiltration are not feasible on-site BMPs as the minimum design requirements cannot be met. Permeable
pavement, bioretention, and rain gardens were deemed infeasible per the infiltration testing in the geotechnical
report. Limited infiltration is deemed infeasible due to the till soils. Basic dispersion may be feasible. If feasible,
basic dispersion should be implemented to the maximum extent feasible which may be more than 10% of the
total lot area. Feasibility of on-site BMPs for each lot will be reviewed at the time of single family building
permit. The restricted footprint BMP can still be used in addition to receive the 10% lot area modeling credit
when sizing the detention vault. Final TIR should clearly explain how target surfaces from plat infrastructure
(road and sidewalk) are mitigated by on-site BMPs or how BMPs are infeasible for these surfaces.
3. A geotechnical report evaluating site soil conditions was prepared by Earth Solutions NW LLC dated February 23,
2017 and a Geotechnical Infiltration Evaluation prepared by Earth Solutions NW LLC dated July 13, 2017. The
report describes the site’s erosion hazard level as low. The soils on site were described as 4 to 10 inches of organics
over medium dense silty sand with gravel and dense poorly graded sand were encountered extending to the
maximum exploration depth of 11.5 feet below existing grade. There was approximately 1.0’ to 4.0’ of fill
encountered in the northwest portion of the site. Earth Solutions NW LLC evaluated onsite soils for infiltration
using the “Pilot Infiltration Testing” at four locations. The Pilot Infiltration Test is an approved infiltration testing
procedure per Section C.1.3 of the RSWDM. No infiltration was observed in three out of the four locations. At
the fourth location (TP-104, located in the southeast portion of the site) there was limited infiltration however
advancing the test pit deeper than the infiltration test depth resulted in an observed confining layer of silt that
limits the capacity of the underlying subgrade to infiltrate. It is the geotechnical engineer’s opinion that this
confining soil layer can result in lateral migration of water which can create flooding rated issues on the
neighboring properties to the south of the subject site since it is sited lower in the elevation than the subject
property.
4. The report concludes that infiltration of stormwater and low impact development (LID) techniques at the site are
infeasible.
5. There is an existing Unspecified Drainage Conveyance System flowing through the project site that appears to
convey upstream tributary from 160th Avenue SE. The Applicant is proposing to capture and convey this upstream
flow to the downstream conveyance system via a storm water piped system that will be routed through the future
proposed right of way through the project site. The size of the bypass conveyance system shall be determine in
accordance with the RSWDM and provided as part of the Civil Construction Permit Application.
6. A Construction Stormwater Permit from Department of Ecology is required if clearing and grading of the site
exceeds one acre.
TRANSPORTATION
1. Each new lot is subject to a transportation impact fee. The 2018 transportation impact fee is $5,430.85 per single
family home. A credit for one lot will be issued due for the existing home. The transportation impact fee is due
at the time of building permit issuance for each individual home.
2. The proposed development fronts 160th Ave SE along the west property line(s). 160th Ave SE is classified as a
Residential Access Road. Existing right-of-way (ROW) width is approximately 60 feet, which satisfies the RMC 4-6-
060 required minimum required ROW width of 53 feet. No additional right-of-way fronting the site will be
required. To provide consistency with the existing pavement width in the corridor adjacent to the project site, a
half street paved width of 16 feet, gutter, 0.5 feet wide curb, 8 feet wide landscaped planter, 5 feet wide sidewalk,
street trees, storm drainage improvements and undergrounding of any overhead utility lines along the frontage
of the property are required on the project frontage.
3. The proposed development fronts 162nd Ave SE along the east property line(s). 162nd Ave SE is classified as a
Residential Access Road, and is an unimproved right-of-way. Existing right-of-way (ROW) width is approximately
60 feet, which satisfies the RMC 4-6-060 required minimum required ROW width of 53 feet. Per RMC 4-6-060, a
paved half street width of 13 feet, a 0.5-foot curb, an 8-foot planting strip, an 5-foot sidewalk, street trees, storm
drainage improvements, and undergrounding of all utilities are required on the project frontage. However, the
applicant has submitted a street modification request to allow the existing street and frontage section to remain.
ADVISORY NOTES TO APPLICANT
Page 6 of 6 LUA**-000***
The modification was requested due to the presence of the stream that runs through the ROW and altering the
existing conditions of 162nd Ave SE would impact the stream and the adjacent critical area. Staff supports the
requested modification.
4. A dead end public street with 53 feet ROW width and 26 feet wide pavement is proposed for the internal site
access. 0.5 feet wide curb, 8 foot wide planters and 5 foot wide sidewalks are proposed on both sides of the
internal street. The proposed widths meet the minimum required widths mentioned in RMC 4-6-060.
Undergrounding of all utilities is required.
5. Current City of Renton standards require a cul-de-sac turnaround for dead-end streets greater than 300 feet and
less than 500 feet. Reference RMC 4-6-060H.
a. Cul-de-sacs shall have a minimum paved and landscaped radius of 45 feet with a right-of-way radius of 55
feet for the turnaround.
b. The cul-de-sac turnaround shall have a design approved by the Administrator and Fire and Emergency
Services.
6. Refer to City code 4-4-080 regarding driveway regulations.
a. A minimum separation of 5 feet is required between driveway and the property line.
b. Maximum driveway slopes shall not exceed 15%. Driveways exceeding 8% shall provide slotted drains.
c. The maximum width of single loaded garage driveway shall not exceed nine feet (9') and double-loaded
garage driveway shall not exceed sixteen feet (16').
7. Street lighting is required from a development that includes more than 4 residential units. A photometric study
and street lighting plan per City standard shall be submitted at the time of construction permit review.
8. All ramps and sidewalks shall be designed in accordance with ADA Regulations.
9. Paving and trench restoration within the City of Renton right of way shall comply with the City’s Restoration and
Overlay requirements.
GENERAL COMMENTS
1. The fees listed are for 2018. The fees that are current at the time of the respective permit issuance will be levied.
Please see the City of Renton website for the current fee schedule.
2. Retaining walls that are 4’ or taller from bottom of footing and stormwater detention vaults will require a
separate building permit. Structural calculations and plans prepared by a licensed engineer will be required as
part of the building permit review.
3. All civil plans shall conform to the current City of Renton survey and drafting standards. Current drafting standards
can be found on the City of Renton website.
4. A separate plan submittal will be required for a construction permit for utility work and street improvements. All
plans shall be prepared by a licensed Civil Engineer in the State of Washington.
5. Please see the City of Renton Development Engineering website for the Construction Permit Application and
Construction Permit Process and Submittal Requirements. Please contact the City to schedule a construction
permit intake meeting.
6. All utilities serving the site are required to be undergrounded.