HomeMy WebLinkAboutSWP272312(2) TECHNICAL INFORMATION REPORT
S?IA FORREST CRESTE
RENTON WASHINGTON
PROJECT 90-74
PREPARED FOR:
--- MR. RAY LABLANC
11621 SE 47TH PLACE
BELLEVUE WA 98006
( 206) 746-2556
PREPARED BY:
PACIFIC ENGINEERING DESIGN INC.
130 ANDOVER PARK EAST SUITE 300
SEATTLE WA 98188
( 206) 432-7970
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OCTOBER 5 , 1992
RECEIVE ®
DEC 0 7 1992
BUILDING DIVISION
TABLE OF CONTENTS PAGE
I . PROJECT OVERVIEW . . . . . . . . . . . . . . . .
II . PRELIMINARY CONDITIONS SUMMARY . . . . . . . . .
OFF SITE ANALYSIS . . . . . . . . . . . . . . . .
IV . RETENTION/DETENTION ANALYSIS . . . . . . . . . .
V. CONVEYANCE SYSTEMS ANALYSIS . . . . . . . . . . .
VI . SPECIAL REPORTS AND STUDIES . . . . . . . . . . .
VII . BASIN AND COMMUNITY PLANNING AREAS . . . . . . .
VIII . OTHER PERMITS . . . . . . . . . . . . . . . . . .
IX. EROSION/SEDIMENTATION CONTROL DESIGN . . . . .
X. BOND QUANTITY WORK SHEET, RETENTION/DETENTION
FACILITY SUMMARY SHEET AND SKETCH, AND
DECLARATION OF COVENANT . . . . . . . . . . . . .
XI . MAINTENANCE AND OPERATIONS MANUAL . . . . . . . .
Page 1 of 2
King County Building and Land Development Division
TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
ProjectOwner QA-1 UA(%,N-n( ProjectName
Address I I�ZI Sf--. 4-JT�l 9LIL Location
Phone &rLLEyL,,f i—/\ 112006, :24 Township 23
Project Engineer e)l,(. 02T1 Range S r
Company � Li�+c rn(,�d1r�GLthc (�rSi(�l� I r1C Section S'v i 0
—r Project Size 12 AC
Address Phone 13D A')IOOL,-r,2 k G -&3 00 Sr A L.,q Q ) O Upstream Drainage Basin Size 2-4- AC
- . .
Subdivision 0 DOF/G HPA Shoreline Management
Short Subdivision COE 404 Rockery
Grading DOE Dam Safety ® Structural Vaults
�( Commercial 0 FEMA Floodplain Other
CJ Other 0 COE Wetlands HPA
Community
2 r
Drainage Basin
River Floodplain
Stream ® Wetlands
Critical Stream Reach 0 Seeps/Springs
Cj Depressions/Swales 0 High Groundwater Table
Lake 0 Groundwater Recharge
a Steep Slopes 0 Other
Lakeside/Erosion Hazard
Soil Type Slopes Erosion Potential Erosive Velocities
°7n Mo{X 2N-Tfz - Sf-,-vre 2-3 rr�
Cl Additional Sheets Attatched
1/90
Pago 2 of 2
King County Building and Land Development Division
TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
REFERENCE LIMITATION/SITE CONSTRAINT
0 Ch.4-Downstream Analysis
a
0
0
a
0
0 Additional Sheets Attatched
MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS
DURING CONSTRUCTION FOLLOWING CONSTRUCTION
Sedimentation Facilities ® Stabilize Exposed Surface
21 Stabilized Construction Entrance 21 Remove and Restore Temporary ESC Facilities
® Perimeter Runoff Control ® Clean and Remove All Silt and Debris
Clearing and Grading Restrictions Ensure Operation of Permanent Facilities
�] Cover Practices ® Flag Limits of NGPES
C� Construction Sequence 0 Other
0 Other
i
� Grass Lined Channel Tank Infiltration Method of Analysis
® Pipe System Q Vault ® Depression
® Open Channel Energy Dissapator ® Flow Dispersal Compensation/Mitigation
0 Dry Pond Wetland 0 Waiver of Eliminated Site Storage
Wet Pond 0 Stream 0 Regional Detention
Brief Description of System Operation Q�7in S7� R Ln�--f in y&'1A �i S- 2C4.-rr, r�
h r%i-f=iLTT PZ5 P2;IA'C,-M ntSt nN2i�3 6{
Facility Related Site Limitations Additional Sheets Attatched
Reference Facility Limitation
i'-71 Drainage Easement
Cast in Place Vault Other Access Easement
® Retaining Wall ® Native Growth Protection Easement
® Rockery>4'High Tract
0 Structural on Steep Slope 0 Other
I or a civil engineer under my supervision have visited the site. Actual
silo conditions as observed were incorporated into this worksheet and the �: �l d
attatchments. To the best of m knowledge the information provided �l�t� OCT�C 1�7�1?
here is accurate. SlynedD�fe
1/90
I . PROJECT OVERVIEW
THIS SITE IS LOCATED AT THE EASTERLY EDGE OF THE CITY OF RENTON .
THE WESTERLY PROPERTY LINE ABUTS DUVALL AVE NE (SE 138TH AVE) . THE
SOU^1HERLY PROPERTY LINE ABUTS THE TO BE CONSTRUCTED 6TH STREET .
THE TOTAL SITE AREA IS APPROXIMATELY 12 ACRES WITH APPROXIMATELY 11
ACRES BEING DEVELOPED . THE REMAINING 1 ACRE IS A TYPE 2 WETLAND
AND BUFFER LOCATED ADJACENT TO THE SOUTHWEST PROPERTY CORNER. THE
SLOPE RANGES FROM 8 TO 11 PERCENT SLOPING DOWNWARD TOWARD THE WEST
AND SOUTH . THERE IS ONE SMALL STALL AND SHED LOCATED NEAR THE
NORTHEAST PROPERTY CORNER. MOST OF THE SITE IS CURRENTLY OVERGROWN
WITH 'FREES AND UNDERBRUSH . THERE IS A SMALL AREA AROUND THE STALL
AND SHED THAT IS OVERGROWN WITH GRASSES .
THE SITE IS TO BE DEVELOPED INTO A 192 UNIT APARTMENT/CONDO PROJECT
WITIi TWENTY BUILDINGS LOCATED THROUGHOUT THE SITE .
THE SITE DRAINS IN SHEET FASHION TOWARDS THE WEST AND SOUTHWEST.
RUNOFF ENTERS THE WETLAND LOCATED ADJACENT TO THE SOUTHWEST
PROPERTY CORNER . THERE ARE TWO EXISTING AREAS THAT DISCHARGE
RUNOFF ONTO THE SITE: 1) 138TH PLC SE AND 2 ) 140TH AVE SE. THESE
UPSTREAM FLOWS WILL BYPASS ON-SITE DETENTION AND--BE ROUTED DIRECTLY
TO THE EXISTING WETLAND.
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"Reproduced with permission granted by THOMAS BROS. MAPS.
This map is copyrighted by THOMAS BROS. MAPS. It is unlawful
to copy or reproduce all- or any part thereof, whether for
personal use or resale, without permission."
II . PRELIMINARY CONDITIONS SUMMARY
CITY OF RENTON
�i Planning/Building/Public Works Department
Earl Clymer, Mayor Lynn Cuttmann,Administrator
September 21, 1992
Mr. Ray LaBlanc
11621 SE 47th PI
Bellevue, WA 98006
SUBJECT: Forrest Creste
ECF;SA-093-88
Dear Mr. LaBlanc:
Attached herein is a copy of the mitigation measures that were adopted by the Environmental Review
Committee at its regular meeting on September 16, 1992. These measures will apply to all proposed
development actions identified in the Draft and Final EIS. The measures will apply to the first permit,
ostensibly a Special Permit for Fill and Grade, and will continue to be applied with all subsequent
permits.
This mitigation document is an appealable action. Appeals should be filed with the City of Renton
Hearing Examiner by October 12, 1992, 5:00 p.m.
If you have any questions about these mitigation measures or the appeal process, please contact Donald
Erickson, Principal Planner and Secretary to the Environmental Review Committee or Lenora Blauman,
Project Manager, at 235-2550.
Sincerely,
t/
aw
Donald K. Erickson, AICP
Secretary to the ERC
i
cc: Washington State
Department of Ecology
Environmental Review Section
Mail Stop PV-11
4
Olympia, WA 98504
ISSULTR
200 Mill Avenue South - Renton, Washington 98055
I
I
FORREST CRESTS
MULTI -FAMILY RESIDENTIAL
DEVELOPMENT
44,
I` _ -
.� .77
1
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. I
E i
U�IY % MITIGATION DOCUMENT I
" ISSUED SEPTEMBER 22, 1992
BY THE CITY OF RENTON
i
i
MITIGATION DOCUMENT
FORREST CRESTS MULTI-FAMILY RESIDENTIAL DEVELOPMENT
The Environmental Review Committee for the City of Renton issued a Final Environmental Impact Statement for the
Forrest Creste Development on September 16, 1992. The EIS for this project has identified a number of possible
mitigation measures for adverse environmental impacts that were considered to be significant or potentially significant
(as defined by quantitative measures whenever such measures were found to exist). In some cases, such measures do
not exist and it was left up to the responsible official to determine whether additional mitigation measures, if any, are
warranted to protect the environment.
A number of chapters of WAC 197-11 speak directly to the imposition of mitigation measures. The relevant chapters are
cited below.
WAC 197-11-060 Content of Environmental Review states that agencies shall "carefully consider the range of
probable impacts, including short-term and long-term effects." Impacts shall include "those that are likely to arise
or exist over the lifetime of a proposal', or, in some cases, even longer.
WAC 197-11-330 Threshold Determination Process requires the responsible official to take into account the
following when determining whether a proposal has significant adverse impacts: "The same proposal may have
a significant adverse impact in one location but not in another location;" "The absolute quantitative effects of a
proposal are also important, and may result in a significant adverse impact regardless of the nature of the
existing environment"; and, "Several marginal impacts when considered together may result in a significant
adverse impact." In reaching such a decision, SEPA states that the responsible official shall not balance whether
the beneficial aspects of a proposal outweigh its adverse impacts, but rather, shall consider whether a proposal
has any probable significant adverse environmental impacts under the rules stated above.
WAC 197-11-448 Relationship of EIS to other considerations states that the general welfare, social, economic,
and other requirements and essential considerations of state policy will be taken into account in weighing and
balancing alternatives and in making final decisions. . . . The EIS provides a basis upon which the responsible
agency and officials can make the balancing judgment mandated by SEPA, because it provides information on
the environmental costs and impacts.
WAC 197-11-660 Substantive Authority and Mitigation requires that mitigation measures be based on policies,
plans, rules or regulations formally designated by the agency. It also requires that mitigation measures shall be
related to specific adverse environmental impacts clearly identified in an environmental document on the
proposal: "After its decisions, each agency shall make available to the public a document that states the
decisions. The document shall state the mitigation measures, if any, that will be implemented as part of the
decisions, including any monitoring of environmental impacts." (WAC 197-11-660(1)(b)) This document is
intended to meet this requirement.
As well as analyzing the environmental impacts, the City of Renton, under its land use provisions, must assess its many
objectives and goals and decide how this project furthers or conflicts with them. Some City goals may be internally
conflicting. When this occurs, the City believes that the SEPA process mandates a close environmental analysis to
determine priorities. If the priorities are established and the project is able to mitigate its impacts sufficiently, then the
City believes it should proceed. This document presents mitigation measures necessary for the ultimate construction of
The Forrest Creste development.
THE PROPOSED ACTION
Raymond t_aBlanc is proposing to develop an 11.93 acre site 1n East Renton as a multi-family residential project
consisting of 24 townhouse condominium units and 176 apartment units. The anticipated residential population living in
Forrest Creste, with the proposed 200 units, is 360 persons. The site is located to the north and generally west of the
Intersection of Duvall Avenue NE and NE 4th Street, and it Is currently covered with second growth vegetation; there are
•.64 acres of wetland (.61 acres of Class II and .03 acres of Class III) on the site. The property Is vacant except for two
outbuildings. The outbuildings and much of the vegetation will be removed for the proposed development. To the west
FORREST CRESTE MITIGATION DOCUMENT 1- SEPTEMBER 22,1992
I
and south of the site are the Orchards Development and the Windsor Place apartment complex; single-family
developments abut the site to the north and the east of the site. Honeydew Elementary School and playground are
located to the northwest of the site.
The project will include a recreation center (with improvements such as lounges, active recreation areas, meeting rooms,
kitchen facilities), a pool, and a sports court centrally located on the site; children's playgrounds are dispersed around the
site. A trail system will be installed throughout the site, providing an area from which to observe the wetlands, as well as
a system for bringing pedestrians to recreational facilities and to neighboring residential units in the Forrest Creste
complex.
Infrastructure improvements will include improvements to Duvall Avenue (turn lanes, sidewalks, street lighting), the
addition of internal driveways/circulation routes, and parking areas), and water, fire, and sewer systems. Additionally, the
applicant will be called upon to support the construction of NE 6th Street, as/if required by City Council following discrete
City evaluation of the requirements and location for this roadway.
The project requires a rezone from G-1, General Use, to R-3 (Medium-Density Multi-Family Use), a designation which is
generally compatible with the current Comprehensive Plan. The applicant is also seeking site plan approval for the
proposed multi-family residential complex.
Development on this site would be ensured to be in general compliance with the City's existing plans and programs by
the establishment of environmental mitigation measures in this Mitigation Document and/or with conditions applied at the
time of site plan review.
Following is a discussion of environmental elements/impact areas, as identified in the Environmental Impact Statement,
togetherwith a presentation of mitigation measures designed to address potential adverse impacts:
A. NATURAL ENVIRONMENT
1. Earth
Impacts: The site is on a portion of the upland between May Creek and the Cedar River. Surface soils
on the site are classified as gravely and sandy; underlying soils are composed of Vashon till (loosely
sorted, highly condensed material deposited on the site about 15,000 years ago). The site slopes
approximately 10%, from a height of 455 feet in the northeast comer to a low of 395 feet in the
southwest comer. Seismic hazard is low on this site.
Grading activities necessary to prepare the site for development would result in some changes to
topography to create nearly level surfaces. These activities would result in an increased potential for
erosion and sediments created could reach buildings and on-site wetlands. Site soils are also moisture
sensitive; moisture collection could result in saturation and or erosion.
Mitigation measures established for construction activities are considered to be sufficient to limit erosion
during development. Limited impervious surfaces (approximately 40% of the site), appropriate storm
water management improvements (described in Section A.4 below), and plans for retainedMtroduced
landscaping (described in Section A.5. below) would be sufficient to control erosion following
development of the site.
RECOMMENDED MITIGATION MEASURES:
A.1.a) The applicant shall, in order to reduce the potential for adverse environmental Impacts to the
underlying terrain from preparation and operation of the site, shall provide a grading and filling
plan prepared by a geote engineer. This plan shall be approved by
Planning/Building/Public Works prior to the issuance of site preparation permits for any element
of the proposed action and shall be consistent with the approved Site Plan. All elements of the
Grading and Filling Plan are to remain In force and effect during all site preparation and
construction activities.
FORREST CRESTE MITIGATION DOCUMENT .2• SEPTEMBER 22, 1992
A.1.b) The applicant shall, in order to reduce the potential for impacts to the underlying terrain from
temporary construction activity, prepare a Construction Mitigation Plan. This Plan shall include
the following elements:
1) a temporary erosion control element (e.g., sediment ponds; sediment traps);
2) a temporary drainage element to address seepage;
3) a provision for wheel-washing vehicles prior to leaving the site;
4) a provision for periodic watering of the site to minimize dust generation;
5) a provision for a geotechnical engineer to inspect the site on a weekly basis to ensure
that all approved site preparation plan elements are in full force and effect; the
geotechnical engineer shall submit written reports monthly to confirm that site plan
preparation is proceeding according to plan; additional written reports shall be submitted
in the event of an emergency or in the event that approved plans require modification;
6) a provision to reduce and recycle construction materials and debris, to the greatest
extent feasible to limit dust/debris impacts during the construction process;
7) a written agreement by the applicant acknowledging its obligation to pay to the City a
total of up to $2,000 within 30 days of receipt of invoices from the City for street-cleaning
costs in the event that the applicant does not complete required street-cleaning
activities;
8) written acknowledgment by the applicant of its responsibility for repair of damage to the
public right-of-way, when such damage is defined by the City as having been caused by
construction vehicles serving the project, and with repairs to be provided by the applicant
in a manner which is consistent with City standards;
9) an educational program for equipment operators which emphasizes procedures and
techniques for limiting the impacts to the stability of site terrain and reducing dust
emissions associated with the operation of construction equipment.
The Construction Mitigation Plan is to be approved by the Development Services
Division in advance of issuance of a site preparation/building permit for any element of j
the proposed action. All elements of the Construction Mitigation Plan are to remain in {
force and effect during all site preparation and construction activities.
The acknowledgment for repair of damage to the public right-of-way is to be approved by
the Development Services Division and the City Attorney in advance of the issuance of a
permit for any element of the proposed action.
I
10) Vegetation Management/Remediation Plan. This Plan shall include the following
elements:
(i) A component which clearly delineates tree clearing limits and protected wetland
buffer areas to minimize disruption to vegetation.
(ii) An agreement which confirms the applicant's intent to begin building within 30
days following site preparation, and/or to hydroseed the site within thirty days of
completion of grading activities (and in no instance later than October 1st) in the
event that development of the site is delayed beyond that period of time.
(iii) A surety device equivalent to ten percent (10%) of the value of the plantings to
ensure the reintroduction of native vegetation to the site (of a level and type j
FORREST CRESTE MITIGATION DOCUMENT SEPTEMBER 22, 1992
commensurate with the current vegetation), within one year of the completion of
grading, in the event that construction of the development is not substantially
underway at that time.
The Vegetation Remediation Plan is to be approved by the Development Services
Division in advance of issuance of a permit for any element of the proposed action. All
elements of the Vegetation Remediation Plan are to remain in force and effect during all
site preparation and construction activities.
Note to Applicant #1: The applicant will also be required to comply with the Surface and Storm Water
Drainage Ordinance, which establishes development parameters for site preparation and construction,
including, but not limited to the confinement of site preparation to periods of relatively dry weather, the
establishment of suitable erosion control methods, and requirements for containing exposed soil.
Policy Nexus: WAC 197-11-660; Environmental Review Ordinance, 4-6; Mining, Excavating, and
Grading Ordinance, 4-10; Comprehensive Plan 1.8; Surface and Storm Water Management Ordinance 4-
22; Land Clearing and Tree Cutting Ordinance 4-9.
ADVISORY NOTE: Impacts to the terrain from operation of the proposed development and mitigation,
measures to address those impacts are presented below—see "Ground Water", "Surface Water", "Storm
Water Management", "Wetlands" and "Habitat'.
2. Air
Impacts: The EIS considered the impacts of and possible mitigation measures for air pollution caused by
particulates, carbon monoxide, and construction activities.
Particulates: For this project, particulate levels were obtained from monitoring stations in the Duwamish
Valley (12026 42nd Avenue South) and in Kent, at James Street and Second Avenue. Information was
also obtained for particulate levels that were monitored at the SE. District Health Center at 12015 NE 4th
Street, approximately one mile west of the project site. Samples taken between 1985 and the present
indicated that the background air quality is well within the national primary standard and the national
secondary standard.
Because the project site is in an area of lower traffic congestion than is the monitoring site, it can be
anticipated that air quality is even better at the project site than at the monitoring site.
Data from PSAPCA monitoring activities indicates that emissions from wood stoves and fireplaces in the
residential portions of the project would likely degrade the air quality in the area. Over the past several
years, there has been an increasing number of "bum bans" employed for solid fuel burning devices in
order to protect air quality. Use of gas fireplaces, however, would be acceptable.
Carbon Monoxide: The increased traffic (approximately 1200 trip ends per day) generated by
development of the site will increase the ambient carbon monoxide levels in the area. No monitoring has
been done to confirm actual carbon monoxide levels at the project site. The site is outside a designated
carbon monoxide non-attainment area and is within an "unclassifiable area." This means that modeling
would likely indicate that occasional violations of the standard would occur.
Construction Activities: Overall, construction activities could adversely impact air quality through the
generation of dust from land clearing and grading operations, as well as from the movement of
construction vehicles on the site. These impacts will be only temporary in nature however, and are not
expected to have a long-term significant impact on ambient air quality. Since the site is in the City of
Renton's "no bum" zone, no particulate emissions will be generated by the buming of land clearing
debris.
FORREST CRESTE MITIGATION DOCUMENT -4- SEPTEMBER 1092
RECOMMENDED MITIGATION MEASURES:
A.2.a) The applicant shall, in order to address air quality impacts from the operation of the residential
complex, install gas fireplaces, in the event that fireplaces are to be provided. Plans for these
heating units shall be approved by the Development Services Division prior to issuance of
building permits.
Policy Nexus: WAC 197-11-660; Environmental Review Ordinance 4-6; UFC
ADVISORY NOTE. Also see Recommendations A.1 (Earth) to address air quality impacts from
construction activities. See.Recommendations B.2 to address transportation-related air quality impacts
for the operation of the complex.
3. Water
a) Ground Water
Impacts: The project site is located entirely with the City's Aquifer Protection Area, Zone II.
Portions of the site (particularly in the western and northwestern portions of the property) host a
moderate amount of perched ground water — that is ground water which rests on or just below
the surface soils,where they are underlain by Vashon till soil (see "Earth'.
Ground water recharge occurs naturally on the largely permeable surfaces. Where subsurface
water is perched, construction of subsurface improvements could be complex, but is feasible.
Additionally, with the project, there will be some loss of recharge due to the increased amount of
impervious surface (about 41% of the site would likely be converted to constructed surfaces with
the proposed development). Long-term slow surface water flow rates will be changed to rapid
short-term flow rates with some accompanying loss of recharge. The contaminants entering the
ground water from the project are expected to be of the type generally found in residential areas
and to pose no significant threat to the aquifer.
To mitigate construction-related impacts construction mitigation plans will need to be developed
to minimize disruption to the site, to employ erosion control and drainage control facilities, and to
revegetate the site. To mitigate the impact of the increased amount of impervious surface and
of the increased flow rates, the project will need to be designed to include a maximum amount of
native vegetation, and to contain a series of biofiltration swales and detention areas. These are
intended to slow down the rate of water flow, to improve water quality, and to provide for
infiltration, thereby partially offsetting the loss of ground water recharge.
Forrest Creste would be subject to the provisions of the Aquifer Protection Area Ordinance. To
reduce adverse impacts on the aquifer, the project does not propose any uses which involve the
lame scale storage of regulated compounds prohibited in APA Zone II. Additionally, the project
will provide sewer service for all uses on the site.
RECOMMENDED MITIGATION MEASURES:
A.3.a) The applicant shall, in order to ensure the protection of water quality in the City's aquifer,
provide each tenant with information concerning the presence of the underlying Aquifer
Protection Area, with a copy of the City's public information brochures concerning the i
Aquifer Protection Area Ordinance, and with notice of the requirement for compliance
with that Ordinance.
A.3.b) The applicant shall provide a central vehicle wash/service area, with containment
facilities, to prevent used water and contaminants from entering the surface water,
groundwater or wetland areas.
Policy Nexus: Aquifer Protection Area Ordinance
FORREST CRESTE MITIGATION DOCUMENT •5• SEPTEMBER 22, 1092
AOVISOPY NOTE: Also see Recommendations A.1 (Earth) and A.4 (Wetlands) to address
ground water quality impacts from construction activities. Adequate mitigation of potential
ground water impacts, including the restriction on the storage or production of regulated
compounds, will be also be achieved through required compliance with the City of Renton
Aquifer Protection Area Ordinance. No other mitigation measures are considered necessary tc
address ground water impacts.
b) Surface and Storm Water
Impacts: The site is located within the upland portion of the Maplewood Creek drainage basin.
Hydrology studies indicate that little runoff currently occurs at the site. However, during heavy
storms, drainage from approximately ninety percent (southernmost 9.3 acres) of the site travels
into a low area on the southwest comer of the site and then into a ditch along the east side of
Duvall Avenue NE. Drainage from approximately 1.2 acres on the southwest corner of the site
travels off of the subject property to the south. The northwest portion of the property
(approximately 1.4 acres) drains into the Duvall Avenue NE ditch at the north end of the
property. Drainage then moves through the ditch in a southerly direction.
There are approximately 24.7 acres of neighboring property to the north and east of the site
which contribute drainage flows which cross the subject property. Approximately 19 acres of that
nearby property is developed with residential uses; the remainder is vacant, forested area.
There is an intermittent stream in the vicinity of the northeast comer of the site. A drainage
channel which runs through the center of the Forrest Creste site conducts runoff from
approximately 10 of the 24.7 acres identified.
f Runoff from the site and tributary areas runs along the above-described ditch on the east side of
Duvall Avenue to a point approximately 600 feet south of the site, where the channel crosses
Duvall Avenue NE through a culvert and travels west for about 1200 feet through heavily
vegetated land at a relatively flat slope. The channel also receives inflows from the area west of
Duvall Avenue NE to the north. It then travels south, crosses NE 4th Street and joins with
--y; Maplewood Creek approximately 2,500_feet downstream from the site. The creek then flows
south through a steep ravine, crosses the Maplewood Golf Course and enters the Cedar River.
At the current time, there is occasional flooding near the culvert crossing (Duvall Avenue/north of
NE 4th Street) and east of the Duvall Avenue/NE 4th Street intersection. Localized flooding has
also been identified in the areas of the ravine and the golf course. There has also been some
flooding and scouring from erosion noted at the Windsor Place Culvert that flows under
Bremerton Avenue NE on the shared boundary between the recently approved Orchards and
Windsor Place apartments.
The existing drainage patterns will be modified on the site during periods of construction activity
—1` (e.g., reconfiguration of soil slope) and during operations (based upon the increased volumes
and changed routes, occurring from the greater amount of impervious surface in the completed
project). However, as a result of required Construction Mitigation Plans, and development-
related improvements required to the site under the City's Surface and Storm Water Drainage
Ordinance (modeled on the King County Surface/Storm Water Management Ordinance
(KCSWM]) the character and quality of storm water runoff will likely be improved above what it
is now on the site in its natural state. With the proposed development, the peak runoff rate from
the developed site will be required to be no greater than pre-development peak run-off rate.
Specifically, in establishing a storm water management system for this site, the applicant will be
called upon to provide a Level 2/Level 3 storm drainage analysis and a solution, consistent with
the KCSWM. This solution would entail provision of a wet pond and detention pond
(approximately 100' x 190' x 51), control structures, oil/water separators and a series of
bioriltering drainage swales, to be coordinated with wetlands, so that these sensitive areas are
not endangered. It would also be desirable to employ the existing natural drainage channel and
to have an infiltration system, if feasible to do so, and if the underlying aquifer could be protected
FORREST CRESTE MITIGATION DOCUMENT g.
SEPTEMOER 22, 10:1_
with such a system. The necessary studies will be provided and conceptual plans developed and
approved by the City in conjunction with site plan review (as required by the City's Surface and
Storm Water Management Ordinance).
Additionally, the City's Utility Systems Division has determined, through the Maplewood Creek
Drainage Basin Study, that increasing the capacity of the Duvall Avenue culvert would eliminate -A
most flooding problems. The City's proposed Capital Improvement Program includes a plan to � —
improve the culvert; if funding for that improvement is based upon "fair share contributions" on
the part of beneficiaries, then it is likely that Forrest Creste would be included in the district
assessment.
The tributary area to the site also hosts some septic tank systems which are failing, which could
lead to contamination of this site through runoff. King County Health Department and the City of
Renton would work together to address such a circumstance.
RECOMMENDED MITIGATION MEASURES:
A.3.c) _No__specific mitigation measures for surface/storm water management are required in
conjunction with the Environmental Mitigation Document as mitigation of on-site adverse
will be achieved through compliance with the City Surface and Storm Water
Management Ordinance (4-22).
Note to Applicant #2: Under the Surface and Storm Water Management Ordinance,
improvements will be required to address on-site surface/storm water impacts and off-
site adverse surface/storm water impacts (both in the local areas of the drainage basin
and in the downstream section of the basin)
Required storm water management analyses and improvement systems (e.g., detention
ponds, control structures, swales) will be conducted and improvements planned/installed
in keeping with the requirements of the King County Surface Water Design Manual
(KCSWM), as established in the City's Surface and Storm Water Management
Ordinance. By Ordinance mandate, conceptual storm water management plans must be
approved in conjunction with site plan review. Also see Recommendations A.1 ("Earth' ,
A.4 ("Wetlands' .
No other mitigation measures are considered to be necessary to address surface/storm water
management impacts.
Policy Nexus: Not applicable
c) Wetlands
1
Impacts: Two wetland areas have been identified on the Forrest Creste site. Wetland #1 is
located next to Duvall Avenue NE on the southwestern comer of the property. Approximately
.61 acres of this wetland area is located within the Forrest Creste property, however, the wetland I,
extends beyond the site boundaries to the south (onto the site of The Orchards); its total size is
approximately three acres. Within the boundaries of Forrest Creste, Wetland #1 is identified as
a Palustrine Forested wetland based upon the United States Fish and Wildlife Service (USFWS)
classification system. The Department of Ecology has designated Wetland #1 as a Class If
wetland — that is, a wetland which is defined by soils, water quality and water quantity which
support wildlife habitat and diverse vegetation communities. Similarly, the wetland would be
identified as Class II or High Quality, under the City's Wetlands Management Ordinance.
i
The on-site portion of this wetland is dominated by red alder, black cottonwood, Oregon ash and
salmonberry. Creeping blackberry, sword fem and lady fem are abundant as well. This wetland
receives water from runoff from the surrounding upland areas. Overflow from the roadside ditch
adjacent to Duvall Avenue NE also appears to accumulate In the wetland. This wetland has
moderately high value for flood control, water quality improvement, and ground water exchange,
4
FORREST CRESTE MITIGATION DOCUMENT -7- SEPTEMBER 1932
Wildlife inventories conducted for this area indicate features which would provide habitat for
passerine birds and a variety of mammals, including mountain beaver, chipmunks and chickaree
during the wet seasons. During this same time period coyote, raccoon, and skunk may hunt the
area for salamanders and Pacific tree frogs. Because of the small size of the wetland and the
limited duration of the period of standing water, the wildlife habitat is not outstanding.
Additionally, no endangered or threatened species were identified.
This wetland is planned to remain essentially undisturbed; a small amount of filling may be
required at the south end of the wetland in order to support construction of NE 61h Street.
Environmental impacts related to the development of the roadway (including affects upon
wetlands) will be addressed under a separate study; the roadway study would include an
examination of routes which bypass the wetland areas. The studies related to the expansion of
NE 6th Street are outside of the purview of this project because the new roadway is not required
to allow development of Forrest Creste. In the event that NE 6th Street is developed, and in the
event that filling of Wetland #1 on Forrest Creste is required, it would be subject to conditions
established in the environmental mitigation document for the roadway, and subject to the
conditions listed below as well.
Wetland #2 is located on the northwest comer of the property adjacent to Duvall Avenue. It is
.03 acres in size. It is defined as a "palustrine shrub/scrub wetland" under the USFWS
classification system and is defined as a Class III wetland by the Department of Ecology.
Dominating vegetation includes red dogwood, blackberry, red alder, buttercup and large leaf
avens. Reed Canary Grass and bentgrass are abundant. A portion of this wetland has been
previously filled. The wetland receives water from a roadside ditch on Duvall Avenue to the
north of the site and from adjacent upslope properties to the east. It has a moderate to low value
for flood control and it offers no significant water quality improvement or ground water exchange;
there is no substantial habitat area here. It would be a Class III (or limited quality) wetland under
the City's Wetlands Management Ordinance.
Based upon the .61 acre size and the classification as a high quality wetland under City
standards (Wetlands Management Ordinance No. 4346), and under Department of Ecology and
USFWS, as described above, the applicant is required to provide improvements in a manner
consistent with local Ordinance requirements. Applicable regulations would include the
Wetlands Ordinance, the Landscaping Ordinance and the Surface and Storm Water
Management Ordinance. These documents establish standards for set backs (50 feet for
Wetland #1 which is defined as a Category II or high quality wetland), for plantings, and for
drainage controls. In order to achieve compliance with these regulations, the final Wetlands
Management Plan would be required to accomplish the following objectives:
• To minimize disturbances to existing wetlands that serve a valuable biological or
habitat function;
• To protect wetlands from adjacent uses when such uses could threaten the
biological or habitat value of the wetland;
-
• To ensure that there is no net loss of wetland acreage on the site; •
• To replace, restore or enhance the disturbed portions of existing wetlands;
• To improve the quality of surface waters entering wetlands;
• To improve the quality of surface waters entering the ground water system;
• To ensure the long-term viability of the post-development wetland area;
The proposed development includes a conceptual plan for improvements for Wetland #1 which
can be specifically designed to achieve compliance with the City's Wetlands Ordinance, the
FORREST CRESTE MITIGATION DOCUMENT 0- SEPTEMBER 22,1092
Surface and Storm Water Drainage Ordinance, and related applicable rules and policies; the
proposed action includes the establishment of set back areas, develop and implement planting
plans, install pedestrian trails, develop partial drainage swales, construct a drainage control
structure.
Wetland #2, because of its small size (.3 acres) and its limited quality, is exempt from the
provisions of the Wetlands Management Ordinance, generally; however, wetland itself will not 4
disturbed and buffers will be-amyided. Further, all improvements provided on the periphery of
this wet area e.g., plantings, pedestrian access points, drainage features) will be required to be
complement the wetland ecosystem.
For reference, an exhibit showing the location and size of each wetland is attached.
RECOMMENDED MITIGATION MEASURES:
A.4.a) No specific mitigation measures for wetlands protection/management are required in
conjunction with the Environmental Mitigation Document as mitigation of on-site adverse
impacts will be achieved through compliance with the City's Wetlands Management
Ordinance (No. 4346).
Note to Applicant #3: The Wetlands Management Ordinance requires the applicant to
submit a specific Wetland Mitigation Plan for wetlands, wetland buffers, and drainage
swales indicating Construction details (—i c ding schedule), vegetation plans (except for
unchanged wetlands), hydrologic regime, boundary and buffers (as appropriate) for each
wetland, wetland buffer, and drainage Swale. The Ordinance, similarly, requires the
applicant to develop and implement a five year monitoring plan (e.g., sampling,
reporting) and a surety device commensurate with the value of the plantings to ensure
replacement of materials as necessary. The Wetland Mitigation Plan shall be approved
by the Planning Section of the Development Services Division prior to the issuance of
any site preparation/building permit.
A.4.b) The applicant shall, in order to enhance the value of the wetland as a natural habitat and
as an educational amenity, provide adjacent to Wetland #1, a pedestrian trail and
observation areas (with interpretive signing concerning the purpose and function of the
wetland/native growth protection areas at appropriate locations). The plan shall be
approved by the Development Services Division in conjunction with site plan review,
A.4.c) The applicant shall, in order to limit potential impacts on water quality and wildlife
habitat, not excavate the existing wetland to create an open water component.
Note to Applicant #4: In the event that filling of any portion of Wetland#1 is determined i
to be necessay to accommodate future c92slniciinc�nf N 6th Street the applicant must
develop a Fill Plan which is consistent with requirements established under the Wetlands
IvManag theme theme Ordin he amount of filled and newly-created, enhanced or restored
wetland area shall be determined during the site plan approval process if the
independent studies for NE 6th Street have been completed; if these studies have not
been completed, future supplemental review of wetland fill plans may be required. If
necessary to prevent the filling of wetland areas merely to create a buffer between the
wetland and the new road alignments, adjustments (averaging) of buffers may be
approved by the Planning Section of the Development Services Division next to the road
alignments for NE 6th Street.
In the event that the alignment selected for NE 6th Street, in the environmental review
for that project, does impact the Forrest Creste site, then it is likely that the applicant will
be required to comply, as well, with the conditions mandated in the NE 61h Street study.
FORREST CRESTE MITIGATION DOCUMENT -9- SEPTEMBER 22, 1992
1
Policy Nexus: WAC 197-11-660; Environmental Review Ordinance, 4-6; King County Surface
Water Design Manual; Comprehensive Plan I.B), l.C., I.D., 1.E., I.F., I.G., I.H., III.D., III.E., and
VIII.C.; Wetlands Ordinance.
5. Natural Habitat
impacts: The site is essentially vacant and heavily vegetated. Native upland vegetation includes trees
(middle-aged fir, cedar, maple, vine maple, and alder), large shrubs (vine maple, Oregon grape,
huckleberry, etc.) and a variety of species of undergrowth plants—such as trillium,wild geranium, ferns,
mosses and typical wildflowers. Wetland vegetation, described above, includes alder, maple, fir, salal,
Oregon grape, ferns, and berries; functionally, the wetlands serve as detention ponds for surface water
runoff in the wet seasons of the year.
The wildlife community varies widely but contains species generally found in and adjacent to highly
urbanized areas lacking unique habitat features. Animal species on the site are primarily migratory.
These would include chickaree, chipmunks, coyote, raccoon, rabbit and skunk; amphibian populations
may be found in the area during the wet seasons. Evidence also indicates the possible intermittent
temporary use of the site by mountain beaver and deer. Because of the planned removal of most of the
existing vegetation, the size and composition of the wildlife community will be changed. Most existing
animal communities will avoid migrating to this site, and will move to the remaining habitat areas nearby.
Urban-tolerant animals will remain on the site in landscaped areas and where tree cover is maintained or
replaced. Conversion of the contiguous forested areas into fragmented tree groves within residential
areas will favor edge species of birds.
Based on a preliminary tree survey of the property and on the proposed site plan, a substantial number
of the numerous evergreen and deciduous trees of greater than 8-inch diameter could likely be retained;
similarly, a sizable number of smaller trees would be retained or introduced onto the site. Additional
native vegetation could be retained on the site; new plantings could be based upon a native vegetation
palate. Screening around site boundaries could be designed to facilitate "pass through" by mammals
and birds,while providing privacy and defensible space for Forrest Creste residents and their neighbors.
RECOMMENDED MITIGATION MEASURES:
A.5.a) The applicant shall, in order to limit the impacts of the development on the wildlife community,
work with the Department of Wildlife, to develop a plan for wildlife management (e.g., relocation
where appropriate) during the period of transition of the site from the natural to the built
environment.
A.5.b) The applicant shall, in order to limit the impacts of the development on the existing habitat,
prepare a Landscape Plan which retains significant trees on the site and which provides for a
variety of landscaping elements. The Plan shall be accompanied by:
1) An amended tree survey of the property indicating the evergreen and deciduous trees of
greater than 8-inch diameter at breast height;
2) A tree preservation plan which retains the maximum feasible number of trees of eight
inches or greater in diameter in areas to be retained as open space under the approved
site plan. The plan should indicate each of those trees of eight inches or greater in
diameter that are planned to be retained and those trees of eight inches or greater in
diameter that are planned to be removed In these areas.
3) A plan and restrictive covenant describing proposed performance and replacement
standards for new landscaping elements and retained trees, exclusive of those In
wetlands and wetland buffers,which shall include provisions for:
(i) Replacing all removed trees greater than 12 inches In diameter with three new
two-inch caliper native species trees (primarily evergreen such as Douglas fir or
FORREST CRESTE MITIGATION DOCUMENT .10- SEPTEMBER 22,1092
Cedar) in preserved open space areas (defined as fifteen feet from tho edge of
buildings and/or drives), and maintenance of those trees over the life of the
project.
(ii) Replacing all removed trees greater than eight (8) inches but less than 12 inches
in diameter with two new'2-inch caliper native species trees(primarily evergreen
such as Douglas fir or Cedar); and maintenance of those trees over the life of
the project.
(iii) Providing a landscaping plan which shall contain extensive landscaping around
the perimeter of the project area and at other appropriate locations. Specifically,
landscape elements within the site shall be planned to consist of native
vegetation elements (with an emphasis on species which provide habitat and/or
food sources), to establish a consistent overall character for the proposed project
or for distinct portions of the project. Landscape elements shall also be of
sufficient density, height, and variety to provide year-round screening between
the site and neighboring residential uses and public rights-of-way.
Note to Applicant m5: The Landscape Plan, tree survey, and proposed performance and replacement
standards shall be submitted to the Planning Section of the Development Services Division for review
and approval prior to the issuance of building permits for the development of the approved site plan.
Note to Applicant xS: At the time of site plan review, staff will likely recommend that the applicant be
called upon to provide: a) a landscaping maintenance agreement, to be valid for the life of the project,
which describes pruning systems, fertilization systems, and pest control systems; and b) a landscaping
surety device (equivalent to ten percent of the value of the plantings) to be valid for the life of the project
to guarantee that any new landscaping element that dies during the first three years after installation will
be replaced. A Homeowners'Association will likely be established to implement these requirements.
Policy Nexus: WAC 197-11-660; Environmental Review Ordinance, 4-6; Comprehensive Plan I.C., I.D.,
III.C., and III.D; Landscaping Ordinance 4-31-34; Land Clearing and Tree Cutting Ordinance 4-9.
B. BUILT ENVIRONMENT
1. Land Use/Housing
Impacts: The project requires rezones, site plan approvals, and demolition, filling, grading, and building
permits. The existing zoning is G-1, General Use, which would allow uses such as residential
development, agricultural activities, raising of livestock and a variety of public recreation facilities (e.g.,
golf course). The proposed project includes an application to designate the entire site for R-3 use; the R-
3 zone (Medium-Density Multi-Family) would permit a maximum of 25 multi-family residential units per
acre. The current Comprehensive Plan designates approximately the southem two-thirds of the site — 8
acres — for medium-density multi-family use, which would allow a maximum of 25 units per acre. The
remaining northem one-third (4 acres) of the site is designated for low-density multi-family development
which would allow a maximum density of 12 units per acre. The proposed density level, at 17 units per
acre, would then be generally permitted with both the underlying low-density and medium-density
residential use designations.
Development of this site with residential units would be in keeping with the King County Growth
Management Policies (e.g., designation of the site as an urban growth area, provision of diversity in
housing types). With up to 200 townhouse and traditional apartments, Forrest Creste would provide
needed multi-family housing opportunities.
No significant environmental impacts with respect to land use or housing impacts are identified..
I
FORREST CRESTE MITIGATION DOCUMENT -11- SEPTEMBER 22,1992
RECOMMENDED MITIGATION MEASURES:
B.1.a) No mitigation measures are required with this Mitigation Document.
Note to Applicant #7: In order to ensure continuing compliance with City policies and programs, staff
may recommend in favor of a contract rezone, which establishes development densities and
performance standards, at the time of the Hearing Examiner's review of the rezone application.
Note to Applicant #8: At the time of site plan review, staff may recommend that the applicant be called
upon to provide a modification to the design and siting of structures, landscaping, and other
services/amenities, pursuant to review under the Site Plan Review Ordinance.
2. Transportation
The proposed project is located in a residential area which is in transition from rural and suburban to
more urban level densities. Future development is anticipated to occur at a density commensurate with
the urban designation assigned to this area by King County and the City. Providing adequate roadway
systems is necessary to support local users and through commuters.
Local roadways in the vicinity of and serving the site are NE 4th Street, NE 3rd Street and NE Sunset
Boulevard which serve as major east-west arterial streets. Duvall Avenue NE, Union Avenue NE, and
Monroe Avenue serve as the north-south arterial routes. Studies of the project area were conducted
using Policy Guidelines for Traffic Impact Analysis of New Development. These studies indicate that
current average daily traffic (ADT) for the major roadways in the study area includes 30,000 ADT for NE
4th Street and 34,000 ADT for NE 3rd Street. NE Sunset Boulevard is the third most traveled road, with
traffic volumes of 22,400 ADT. Duvall Avenue NE, adjacent to the proposed Forrest Creste complex,
currently carries 7,000 vehicles. The majority of these trips will originate and end outside of the City of
Renton. The traffic study conducted for the EIS estimates that the project will generate 1235 daily trips
and 137 afternoon peak-hour trips.
When these trips are added to the predicted 1993 traffic volumes at the five area intersections analyzed,
all intersections would continue to operate at Level of Service (LOS) D or better, except that LOS E
could occur at the NE 4th Street/Union Avenue NE intersection at the afternoon peak hour (based upon
anticipated levels of development at sites which would be anticipated to result in additional trips along
this travel corridor). Based on City standards, LOS D or better is considered acceptable, so the project
would generally not cause traffic operations to fall below City standards at intersections in the area. At
the NE 4th Street/Union Avenue intersection, in the event that the anticipated LOS E occurs, it will be
addressed by improvements slated to be installed by the City under the East Renton (NE 3rd/4th Street)
Transportation Benefit District; improvements would be funded by contributions from developments
within the District boundaries or within the "sphere of influence"as described below.
Specifically, staff note that while Forrest Creste is outside of the Benefit District, the City will call for the
applicant to participate in the District to a fair share, based upon study findings which indicate that the
project is in the "sphere of influence" affected by the District, and findings which indicate that there will
be impacts from the project on District roadways. For example, in conjunction with the Benefit District,
the applicant may be called upon to participate in improvements (such as improvements to signalization
and/or monitoring of traffic volumes/pattems) to NE 3rd/4th Street at intersections with Duvall Avenue,
Monroe Avenue, Jefferson Avenue, and Union Avenue should result in protection/creation of satisfactory
service levels.
Additionally, the applicant must make improvements, to City standards, to all surrounding residential
streets and neighborhood collector streets where impacts occur which are directly attributable to the
project For example, the applicant would be called upon to provide an additional eight feet of right-of-
way on Duvall Avenue NE and to install a left turn lane parallel to the project site; lane paving, curbs,
gutters, sidewalks, and street lighting would be required along that corridor as well. These construction
requirements will result in roadways of adequate size and with appropriate improvements (e.g., travel
lanes, turn lanes, signals/signs, curbs, sidewalks, street lighting), to allow safe, efficient movement of
FORREST CRESTE MITIGATION DOCUMENT -12- SEPTEMBER 22, 1992
anticipated vehicular and pedestrian traffic. At the time of site plan review, staff may call upon the
applicant to extend street improvements (curbs, sidewalks, gutters) along Duvall Avenue from the north
property line of the site to the intersection with SE 121st Street; this extension would provide a logical
boundary which would facilitate safer pedestrian travel along this corridor.
Further, the applicant will be called upon to participate in the future construction of the NE 6th Street
extension, in accord with City requirements; this road would be constructed when sufficient fees are
available from both Forrest Creste and the Orchards to install improvements. Future studies conducted
under the direction of the City will determine the design, siting and construction of that roadway.
With respect to on-site vehicle circulation impacts, the applicant is proposing to provide primary access
from Duvall Avenue at this time, with a second access provided from NE 61h Street, when funding is
available to do so. A gated emergency access will be provided on the northeast comer of the site (140th
Avenue NE). The project-generated traffic is projected to use Duvall Avenue NE (either via direct
access and/or via access from the likely extension of NE 6th Street), leading to Sunset Boulevard or to
NE 4th Street. The applicant must construct internal roadways and related on-site improvements curbs,
gutters, sidewalks, general directional signs, and fire lanes) to comply with City codes (e.g., Subdivision
Ordinance 9-12-8; Streets and Arterials Plans): at the time of site plan review, it is likely that the City will
call for a gated bridge over the detention pond to ensure the availability of contiguous roadway for
emergency vehicles.
The applicant has proposed to provide 1.75 designated parking spaces per unit, in accord with
requirements established in the Parking and Loading Ordinance (4-14). Additionally staff will call for the
provision of adequate space for tandem parking adjacent to garages, in a manner which does not intrude
into commuter or emergency vehicle travel lanes. In order to further ensure the continuing availability of
travel lanes for resident's vehicles and emergency service vehicles, the applicant will be required to
provide a vigorous management system for enforcement of parking restrictions and a surety bond in the
amount of 550,000.00 to reimburse the City for costs incurred in enforcement of City regulations. With
these mitigation measures, the project would provide for efficient on-site travel and would not cause any
adverse impacts on the parking supply in the surrounding area. (In the event that the number of units is
reduced, parking spaces would likely be removed from the east side of the property to provide
opportunity for a greater planted buffer between the site and property to the east.)
Pedestrian pathways planned for this project will be designed to provide access to nearby developments,
to public roadways, and to transit stops.
Transit service is provided to the project area by Metro routes #111 and #147 on NE. 4th Street. These
routes provide service to downtown Renton, South Bellevue, and downtown Seattle. According to Metro,
a proposed service change for 1992 has been proposed for route 240 to serve Coal Creek Parkway,
Duvall Avenue NE, and NE 4th Street. This route would operate seven days a week and provide direct
service to downtown Bellevue, and offer connections at the South Renton Park and Ride with Metro
service to downtown Seattle and South King County destinations. This route would become the main
transit service for the proposed project. Provisions for a METRO bus stop will be recommended.
Truck traffic in the area would likely increase during the periods of construction activity. Because this
traffic will operate prior to the installation of any traffic improvements adjacent to the project site, it could
increase the risk of accidents on Duvall Avenue NE and Union Avenue NE. Truck traffic after
completion of the project will be minimal, as it will consist only of delivery vehicles and occasional
moving vans.
To mitigate the increased demand placed on transportation facilities by the uses in the proposed project,
a variety of transportation mitigation measures are being recommended. They can be grouped into the
following categories:
a) Participation on a "fair share" basis In the NE 3rd/NE 41h Street Traffic Benefit Zone in order to
provide support for improvements to the local roadway network (e.g., Duvall Avenue NE., NE 6th
Street construction: signalization improvements at intersections along the NE 3rd Street
corridor); these actions would supplement those improvements required by City Code (e.g., i
Renton Subdivision Ordinance) for the proposed development;
FORREST CRESTS MITIGATION DOCUMENT -13- SEPTEMBER 22,1992
b) Physical improvements to mitigate the dependence on single occupancy vehicles by
encouraging the use of the proposed new transit service on Duvall Avenue NE;
c) A Transportation Management Plan (TMP) designed to decrease the dependence of residents on
single occupancy vehicles;
d) Facilities to encourage the use of bicycles for commuting thereby mitigating the impacts
associated with dependence on automobiles.
Additionally, mitigation measures are proposed to reduce the impacts of construction traffic on adjacent
streets and residential areas.
RECOMMENDED MITIGATION MEASURES:
B.2.a) The applicant shall, in order to reduce project-generated traffic impacts on the NE 3rd/NE 4th
Street corridor, either: i) provide direct improvements to the NE 3rd/NE 4th Street corridor,
pursuant to direction by the City's Transportation Services Division; or ii) contribute a "fair share"
traffic mitigation fee for the NE 3rd/NE 4th Transportation Benefit District of$124.00 per average
weekday trip. The direct improvement plan or the Traffic Mitigation Fee is to be established at
the time of application for a Building Permit for any element of the proposed project. The direct
improvement plan or the fee option is to be based on the number of average weekday trips
attributable to the District from the project. If the applicant elects to construct direct
improvements, they shall be installed prior to the issuance of the Certificate of Occupancy for
the project. If the applicant elects to pay a fee, that fee shall be paid prior to the issuance of the
Building Permit. (Note: The fee would be $153,000.00 for the proposed 200 unit complex,
based upon the 1235 ADT level).
Note to Applicant #9: If the applicant cancels the Building Permit in writing, then the
unencumbered portion of the fee plus accrued interest may be refunded to the applicant.
8.2.b) The applicant shall, in order to reduce project-generated traffic impacts on Duvall Avenue NE
deed up to eight feet of additional right of way, if necessary, on Duvall Avenue NE prior to
widening of the street to five (5) lanes. The applicant shall receive a credit toward the Traffic
Mitigation Fee for the value of any street right-of-way which exceeds that required by City
ordinance(s).
Note to Applicant#10: In addition to the above-described dedication, the applicant will be called
upon to construct roadway improvements on Duvall Avenue NE abutting the site (e.g., curbs,
gutters, sidewalks, street lighting) and install a left turn lane on Duvall Avenue adjacent to the
project site as required by the Renton Subdivision Ordinance (9-12).
At the time of site plan review, staff may also recommend extension of selected right-of-way
improvements (curbs, gutters, sidewalks) along Duvall Avenue north to SE 121st Street in order
to protect pedestrian safety between the site and nearby commercial/institutional developments
which are likely to be utilized by Forrest Creste residents.
B.2.c) The applicant shall, in order to provide necessary secondary ingress/egress to the site,
participate to a fair share in the construction of NE 6th Street as a full width neighborhood
collector street. Participation will include, but may not be limited to dedication of a thirty (30)
foot right-of-way, installation of paving, curbs, gutters, sidewalks and street lighting, installation
of a vehicle turnaround (to standards established in the Renton Subdivision Ordinance), The
applicant shall receive a credit toward the Traffic Mitigation Fee for the value of any street right
of way which exceeds that required by City ordinance(s) OR the applicant shall be reimbursed
through a Latecomers Agreement for the value of any street improvement(s) which exceed that
required by City ordinance(s).
FORREST CRESTE MITIGATION DOCUMENT -14- SEPTEMBER 1992
8.2.d) The applicant shall, in order to reduce traffic Impacts associated with the reliance upon single
occupancy vehicles, provide direct pedestrian access routes from internal residential streets to
Duvall Avenue NE to encourage the use of proposed new transit service on Duvall Avenue NE.
Pedestrian routes to Duvall Avenue NE must have hard surfaces and adequate pedestrian-level
lighting to provide safe use during low light hours. The pedestrian routes and lighting shall be
approved by the Planning Section of the Development Services Division as part of the site plan
approval process.
6.2.e) The applicant shall, in order to reduce traffic impacts associated with the reliance upon single
occupancy vehicles, prepare a Transportation Management Plan (TMP), prior to issuance of the
Building Permit for any element of the project. The TMP must contain at least the following
provisions:
1) A designated transportation coordinator to promote and coordinate the use of public
transportation and high occupancy vehicles; (this person could be a manager or resident
of Forrest Creste);
2) A free one-month bus pass made available to each new tenant at the time of occupancy
(peak hour, two zones);
3) The distribution of site-appropriate transit and ride sharing information to new tenants
and annually to all tenants;
4) Secure bicycle parking in, or reasonably close to, each multi-family structure;
5) An annual transportation survey and monitoring report submitted by the transportation
coordinator to the Transportation Services Division.
B.2.0 The applicant shall, in order to ensure adequate emergency access to the site, provide:
1) a gated entry route via 140th Avenue NE, which is restricted to use by emergency
vehicles. Plans for this access (right-of-way, paving, etc.) shall be approved by the
Development Services Division and the Fire Department during site plan review. This
access route shall be available during construction and operation of the Forrest Creste
development.
2) a reservation of right-of-way of sufficient width to accommodate City street standards for
any future extension of 140th Avenue SE that traverses the subject property; provided
that such reservation shall terminate six years after the issuance of the Certificate of
Occupancy for the Forrest Creste development.
8.2.g.) The applicant shall, in order to ensure adequate emergency vehicle access to the site, shall
provide an emergency services management plan which includes a strong educational
component and vigorous enforcement of parking restrictions to ensure that persons do not park
illegally on this site in areas which are required for circulation and/or emergency vehicle access.
This plan is to be accompanied by a provision for a renewable emergency services protection
surety device, in the amount of$50,000.00, to be instituted following any calendar year in which
ten (10) or more parking citations are issued for Forrest Creste. This device is to be valid for a
minimum three (3) year period from the last reported violation; this plan and surety device are
Intended to assist in ensuring the preservation of the required right-of-way for resident's and
emergency vehicles. The plan and the surety device are to be approved by, and the fee paid to
the Development Services Division prior to the issuance of the Certificate of Occupancy.
8.2.h) The applicant shall, in order to encourage increased use of public transit, contribute a fair share
toward the provision of a concrete base and necessary easement for one transit shelter on
. i
i
FORREST CRESTE MITIGATION DOCUMENT •15- SEPTEMBER M,1092
Duvall Avenue NE. Location of the transit shelter base and easements shall be coordinated with
The Orchards and other neighboring developments; It shall be approved by Metro, and the
Development Services Division, as part of the site plan approval process.
8.2.1) The applicant shall, In order to address traffic safety impacts, work with the Renton School
District to determine a fair share contribution for a school bus shelter on or adjacent to the
project site. Plans for this school bus stop shall be approved by Development Services Division
In conjunction with site plan review for Forrest Creste. The school bus shelter shall be installed
prior to the issuance of the Certificate of Occupancy.
8.2.J) The applicant shall, in order to reduce local and regional traffic impacts (and related dust and
noise impacts) caused by construction vehicles, provide the following plans/systems, to be
approved by the Transportation Services Division prior to issuance of any site
preparation/building permits:
1) temporary traffic control measures on Duvall Avenue NE. during periods of site
preparation and construction;
2) specific planned off-site hauling routes;
3) an internal looped emergency access route to provide emergency services personal
access to all areas of the site at any time during the preparation and construction of the
development;
4) an agreement to confine operation of construction vehicles on nearby residential streets,
limit construction vehicle access to the site to Duvall Avenue NE;
5) an agreement to restrict hauling activities at the 1-405 and NE. 4th Street and at 1-405
and Sunset interchanges to the hours of 8:30 AM to 3:30 PM or submit a hauling route
plan for peak hours which avoids these interchanges; and
6) an agreement.to restrict construction activity on the site to the hours of 7 AM to 8 PM,
Monday through Saturday. No construction activity shall be permitted on Sundays or
holidays.
Policy Nexus: WAC 197-11-660; Environmental Review Ordinance, 4-6; Washington State Second
Substitute House Bill 1671 (SSHB 1671); City of Renton Six-Year Transportation Improvement Program;
City of Renton Resolution 2769; Comprehensive Plan La), Vil.a), VILb), VII.C., and VII.H.; Northeast
Quadrant Plan.
3. Public Services
The EIS identified a number of potential impacts and possible mitigating measures for police and fire
service, schools, and parks and recreational facilities.
a) Police
The project is located in District Nine of the Renton Police Department. This zone is developed
primarily with residential uses. The response time for emergency calls averages just under three
minutes and for non-emergency calls just under ten minutes. This level of service is provided by
a force which averages 1.9 officers per 1,000 population.
The residential project is anticipated to generate 88 annual calls for police service. No increase
In the number of police officers is anticipated to maintain the current ratio of officers to
population, to meet the Increased demand placed by the 360 residents of i-orrest Creste.
FORREST CRESTE MITIGATION DOCUMENT •10- SEPTEMBER Z,I=
In order to ensure that adequate resources are available to serve the residents of Forrest Creste,
staff will recommend that Forrest Creste be required to provide a surety device to emergency
fund service levels above those anticipated for this development.
Additionally staff have recommended the provision of congregate areas which would enable
residents to become acquainted with one another and, thus, be more aware of intruders onto the
site.
Finally, at the time of site plan and building review, staff will make specific suggestions for
improvements such as security devices, lighting, and alarm systems which are useful tools to
reduce crimes against persons and property.
RECOMMENDED MITIGATION MEASURES:
B.3.a) The applicant shall, in order to reduce the potential impacts on the existing police force,
voluntarily provide a renewable extraordinary police services surety device in an amount
of $10,200.00, to be valid for a period of three (3) years, and to be approved by the
Police Department and the City Attorney. The surety device is to be provided prior to
issuance of a Certificate of Occupancy. The surety device will be drawn on in the
amount of$75 for each multi-family residential police service call that exceeds twice the
annual average number of calls per multi-family residential unit in the City of Renton
times the number of units for which a Building Permit is being sought. If the surety
device is drawn on in an amount less than $3,400.00 in the first year or less than
$6,800.00 in the second year, the amount of the device for the subsequent year may be
reduced accordingly.
Note to Applicant #11: If fewer than 200 units are constructed, the amount of the bond will be
reduced accordingly.
' Policy Nexus: WAC 197-11-660; Environmental Review Ordinance, 4-6.
b) Fire
The project is located on the eastern edge of the Renton Fire Department's first response area.
First response fire service would be provided to the project by Fire Station #12 (the Renton
Highlands Station),which is located at NE 9th Street and Harrington Avenue NE. Currently, Fire
Station #12 is staffed by five personnel and is equipped with one engine company and one aid
ca r.
The Fire Department estimates that the proposed project would generate approximately 20
additional calls (e.g., fire, health emergency) per year based on the average number of calls for
projects similar to the proposed 200 unit project. Response time to the project from this station
would range from 5 1/2 to 6 minutes. According to the 1987 Fire Department Master Plan, an
acceptable first response time is defined as having 5 firefighters on the scene in 5 minutes or
less. Acceptable emergency aid response time is defined as having an aid car on the scene in 3
minutes or less.
Mitigation measures would include provision of Code mandated on-site improvements such as
emergency access routes (during construction and operation); hydrants, signage, illumination,
alarm systems, and sprinklers. The provision of management plans and a surety device to
ensure In the preservation of the required right-of-way for emergency vehicle travel will be
required (see Transportation). The applicant will also be required to participate to a fair share
contribution to the City's Fire Benefit District (Resolution #2931) toward the construction of new
fire facilities in the City of Renton. The fee for this project would be $388.00 per unit.
i
FORREST CRESTE MITIGATION DOCUMENT _17• SEPTEMBER 22,1992
RECOMMENDED MITIGATION MEASURES:
B.3.b) No mitigation measures are considered to be necessary in conjunction with
environmental review.
Note to Applicant #12: The applicant will be required by City regulation to install on-site
improvements to address fire prevention/suppression standards and will also be required to
contribute to the Fire Benefit District (pursuant to Resolution#2931) at a rate of$388.00 per unit.
(Also see 'Transportation'
Note to Applicant #13: If the applicant cancels the Building Permit in writing, then the
unencumbered portion of the Fire Benefit District fee plus accrued interest may be refunded to
the applicant.
c) Schools
The proposed project is located within Renton School District No. 403. Students in the area
attend Maplewood Heights Elementary School, McKnight Middle School, and Hazen High
School. Using the Renton School District's student-per-household multipliers, the project would
result in 45 elementary school students, 11 junior high school students, and 10 high school
students. In September of 1990, Maplewood Elementary School was 3 students below capacity,
McKnight Middle School was 285 students below capacity, and Hazen High School was 434
students below capacity.
Depending on the timing of occupancy of the various residential portions of the project and
depending on future enrollment trends, the project could generate a demand for student spaces
for elementary schools which exceeds the capacity of Maplewood Heights Elementary School.
However, as there is a considerable amount of approved residential development underway in
the immediate vicinity of the site and on nearby properties, it is likely that improvements required
to serve Forrest Creste would be in place prior to the development of the project.
The applicant will be encouraged to work with the School District to mitigate project-related
impacts to local schools.
RECOMMENDED MITIGATION MEASURES:
B.3.c) No mitigation measures are established in conjunction with environmental review.
Note to the Applicant #14: The Renton School District (#403) currently has no Mitigation Fee
Plan in place; therefore, there is no nexus which permits the City to assess a mitigation fee for
Forrest Creste. However, the applicant is encouraged to work with the School District to develop
and implement a plan for mitigation of any impacts from the project to the District.
d) Parks and Recreation
The project contains active recreational facilities for the residents of the townhouses and
apartments. For example, a recreation center will be provided which contains facilities such as
an exercise room, lounge, and cabana/meeting room facility. There will also be an outdoor
swimming pool. In addition, one sports court and several children's play areas are provided
throughout the site. Finally, a pedestrian walking/jogging trail winds through the site, providing
both an active exercise amenity and an opportunity to observe the wetlands areas
(benches/interpretive signs).
Passive recreational open space in the project includes the wetlands and buffers and the
landscaped areas surrounding the townhouses and apartment buildings. Additionally, pedestrian
FORREST CREST MITIGATION DOCUMENT -to- SEPTEMBER 22,1992
pathways are planned through each of the apartment areas containing recreational centers;
pedestrian linkages to the nearby Orchards will be encouraged as well, both as a recreational
amenity and to facilitate pedestrian travel/access to public transportation.
Staff will recommend the addition of congregate areas around mail box centers, including
covered benches, lighting and plantings to serve as community gathering centers.
Recreational facilities within a three mile radius include the playgrounds at Honeydew
Elementary School, Kiwanis Park, Windsor Hills Neighborhood Park, Highlands Neighborhood
Park and Community Center, Liberty Community Park, Cedar River Community Park, Gene
Coulon Memorial Beach Park, and the proposed Heather Downs Neighborhood Park.
Maplewood Golf course is also near the site.
RECOMMENDED MITIGATION MEASURES:
B.3.d) The applicant,shall, in order to reduce the potential impacts on existing park and
recreational facilities, pay a Parks Comprehensive Plan Mitigation Fee in effect at the
time of issuance of a Building Permit for each element of the project. If no fee is in
effect at that time, the applicant shall pay an off-site Park Mitigation Fee of $180 per
multi-family unit or provide direct improvements to the equivalent of$180.00 per unit as
approved by the Parks and Recreation Department according to City standards.
Note to Applicant #15: If the applicant cancels the Building Permit in writing, then the
unencumbered portion of the fee plus accrued interest will be refunded to the applicant.
B.3.e) The applicant shall, in order to reduce the potential impacts on existing park and
recreational facilities, deed an additional right of way, if any, necessary to accommodate
a bicycle path on the east side of Duvall Avenue NE. The applicant shall receive a
credit toward any parks mitigation fees for the value of the bike path right(s) of way
dedicated. The amount of the credit shall be determined by the Parks Department.
B.3.0 The applicant shall, in order to reduce the potential impacts on existing park and
recreational facilities, incorporate a system of pedestrian trails in wetland buffers,
portions of wetland buffers, and/or along drainage swales, provided that the trails not
infringe on the inner 20 feet of any buffer. Trails should meet the standards of the Parks
Department. The location of trails shall be approved by the Planning Section of the
Development Services Division and the Parks Department as part of the site plan
approval process and as part of the approval for the Wetland Mitigation Plan.
B.3.g) The applicant shall, in order to improve on site recreational facilities, incorporate
congregate areas around mail box centers, including weather protected seating areas,
pedestrian scaled lighting, decorative paving and plantings to serve as community
gathering centers. Plans for such centers shall be approved by the Development
Services Division in conjunction with site plan review.
Policy Nexus: WAC 197-11-660; Environmental Review Ordinance, 4-6; Comprehensive Plan
VII.H. and IX.D.; Comprehensive Park and Recreation Plan; Bicycle Trails Master Plan.
e) Utilities
The project site presently is not served by water or sewer service. Such services will need to be
provided and Sewer Utilities Connection fees will need to be provided.
1) Water. The water supply for Renton is provided by an aquifer underlying Northeast
Renton. The aquifer provides a reliable water source; water available to the site far
exceeds anticipated use levels. Water mains will need to be extended, as required by
FORREST C''.ESTE MITIGATION DOCUMENT -19- SEPTEMBER 22,1992
City Code, to provide for domestic water use and to ensure adequate now for fire-related
emergencies. The applicant could satisfy City requirements by extending a 12 Inch main
along Duvall Avenue and developing an 8 inch to 12 inch looped water main for fire now.
Fire flow in the vicinity of the site is estimated at 3,000 gpm which is considered
adequate by the Fire Department.
RECOMMENDED MITIGATION MEASURES:
B.3.h) No mitigation measures are required to address environmental impacts, as these
impacts are addressed by Code requirements.
Note to Applicant #16: Special Utilities Connection Charges will be assessed by the
Utilities Engineering Division, following finalization of site plan review, in conjunction
with issuance of the building permits.
2) Sewer. The proposed Forrest Creste site is not currently served by sanitary sewer lines.
It is located in the Heather Downs Drainage Basin an area of East Renton where lines
are operating at or near capacity; a moratorium has been declared on the construction of
new development in this area until sewer capacity can be provided.
However, Forrest Creste and eight other developments in the area have been authorized
by Council as eligible for limited exemption to this moratorium, because development
applications were submitted to the City prior to adoption of Resolution No. 2764 which
established the moratorium. Two options are available to serve Forrest Creste. If
existing remaining sewer capacity is sufficient then the development could connect to
the existing system. Or, interim improvements can be made to increase the available
capacity of the sewer system. City Council must authorize any plan for providing
temporary sewer service to the site.
The applicant has elected to request City Council authorization to participate in the
interim connection program. This program provides a solution which entails an
interbasin transfer of flows from the Upper Heather Downs basin to the Lower
Maplewood basin. To accomplish this transfer, it is necessary to construct a lift station
on a parcel to the south of the adjacent Orchards site as well as a force main from this
lift station to the intersection of NE 2nd and Monroe Avenue. The improvements will be
financed by the developers of Forrest Creste and the developers of other projects (e.g.,
The Orchards) which will benefit from the improvements. When the East Renton
interceptor (or an alternative permanent service line) is constructed, Forrest Creste
would be required to connect to that permanent system.,
RECOMMENDED MITIGATION MEASURES:
B.3.i) No mitigation measures are required in conjunction with environmental review.
Note to Applicant #17: In the absence of standard sewer systems, the applicant will be
required to participate in the interim program authorized by Council Resolution 2764, or,
develop an altemative system for provision of sanitary sewer service in accord with local
regulations.
FORREST CRC:'rE MITIGATION DOCUMENT •20- SEPTEMBER 22, 1092
III . DOWNSTREAM ANALYSIS LEVEL ONE
THE LARGER NORTHERLY DRAINAGE BASIN HAS APPROXIMATELY 10 ACRES OF
DEVELOPED AREA THAT DRAINS DIRECTLY TO THE SOUTHWEST WETLAND. THE
SMALLER SOUTHERLY DRAINAGE BASIN HAS APPROXIMATELY 1 ACRE OF
DEVELOPED AREA. THIS BASIN DRAINS SOUTHERLY FOR APPROXIMATELY 300
FEET AND ENTERS A TYPE 2 WETLAND. THIS WETLAND IS PART OF A LARGER
WETLAND WHICH THE ENTIRE SITE DRAINS TO.
RUNOFF FLOWS FROM THIS WETLAND SOUTHERLY APPROXIMATELY 600 FEET
ALONG THE EAST SIDE OF DUVALL AVE NE. THEN RUNOFF CROSSES UNDER
DUVALL AVE NE THROUGH A 36" CULVERT AND FLOWS APPROXIMATELY 800
FEET SOUTHERLY AND WESTERLY THROUGH HEAVILY A VEGETATED AREA AND A
THE RECENTLY CONSTRUCTED WINDSOR APARTMENT COMPLEX. FROM THERE
RUNOFF ENTERS A 24" CULVERT AND FLOWS WESTERLY UNDER THE WINDSOR
SITE. RUNOFF CONTINUES FLOWING FOR APPROXIMATELY ANOTHER 400 FEET
WESTERLY TO NE 4TH STREET. FROM THERE RUNOFF FLOWS SOUTHERLY UNDER
NE 4TH AND TNT AN OPEN AREA, SINGLE FAMILY DETENTION POND AND ON TO
MAPLEWOOD CREEK. MAPLEWOOD CREEI{ IS IDENTIFIED AS A TYPE 2 STREAM
APPROXIMATELY 2 MILES DOWNSTREAM FROM THE SITE . FROM THAT POINT
RUNOFF CONTINUES WITHIN MAPLEWOOD CREEK FOR APPROXIMATELY ANOTHER
400 FEET TO THE CEDAR RIVER AND ON TO LAKE WASHINGTON .
a •
IV . RETENTION/DETENTION ANALYSIS AND DESIGN
THIS SITE HAS BEEN DESIGNED USING THE 1990 KING COUNTY DRAINAGE
MANUAL & THE CITY OF RENTON ' S WETLAND, BUILDING, AQUIFER AND
DRAINAGE CODES . RUNOFF IS ROUTED THROUGH TWO SEPARATE DETENTION
SYSTEMS AND BIO-FILTER SWALES PRIOR TO ENTERING THE WETLAND OR
DOWNSTREAM CORRIDOR. THE DETENTION SYSTEMS HAVE BEEN DESIGNED TO
RELEASE RUNOFF AT THE PRE-EXISTING CONDITION UP TO AND INCLUDING
THE 100 YEAR EVENT . THIS HAS BEEN DONE, PER THE CITY OF RENTON ' S
REQUEST, TO PRECLUDE ANY RECONSTRUCTION OR UPGRADING OF THE DOWN
STREAM SYSTEM.
RUNOFF WILL BE DETAINED IN TWO SEPARATE BELOW GROUND VAULT SYSTEMS .
THIS WAS ALLOWED BECAUSE THE DOWN STREAM SYSTEMS, WITHIN ONE MILE,
ARE NEITHER TYPE 1 WETLANDS NOR TYPE 1 OR 2 STREAMS .
RUNOFF EXI^tING THE DETENTION SYSTEMS WILL FLOW THROUGH BIO-FILTER
SWALES . THESE SWALES HAVE BEEN DESIGNED FOR MAXIMUM FILTRATION
DURING THE 2 YEAR EVENT AND CONVEYANCE OF THE 100 YEAR EVENT . ONCE
RUNOFF LEAVES THE SWALES FLOW WILL ENTER EITHER A FLOW SPREADER OR
LEVEL SPREADER.
THE TWO OFF-SITE CONTRIBUTING AREAS WILL BE ROUTED THROUGH THE SITE
VIA PIPE OR OPEN DITCH. BOTH OF THESE AREAS WILL BYPASS DETENTION
AND PLOW DIRECTLY TO THE WETLAND AREA. THE NORTHWESTERLY AREA WILL
BE ROUTED THROUGH THE NEW STREET FRONTAGE IMPROVEMENTS .
KING COUNTY, W HINGTON, SURFACE WA R DESIGN MANUAL
RETENT WDETENTION SUMM RY SHEET
Development 1�-�22 r 5'T ' G S Date OC 'S-,
Location rAST SOS !it- OLVAUI. /00n,71/ So h C-' 67h ST
ENGINEER DEVELOPER
Name &A- M T H Name (24`�/ LA 6-uA`)j(.
Firm PAC/ In-��Gsi;ln� �`S)✓ I" li)b Firm
Address 130 A-2100M(l ��� r -f-3C0 Address )I GZ I S r 1-71ti &L
Phone 431--Z"20 Phone -25S�
• Developed Site acresNumber of Lots 1
• Number of Detention Facilities On Site 2
• Detention provided in regional facility 0
Regional Facility location Do-
• No detention required ❑
Acceptable receiving waters
• Downstream Drainage Basins
Immediate Major Basin
Basin A &r 0h 2.
Basin B
Basin C
Basin D
TOTAL INDIVIDUAL BASIN
Drainage Basin(s) A B C D
Onsite Area 10 QC I A
Offsite Area
v�t,t,T vAw i
Type of Storage Facility
Live Storage Volume Z , 3 cr- cr
Predeveloped Runoff Rate 2year 66 cr5 s cr-S
10year I.qZ I� "
Postdeveloped Runoff Rate 100 year 3 .3)
2 year .3
10 year S•S .�6
Developed Q 100 year S,¢¢ '' °►S
Type of Restriction 0elf--I
Size of Orifice/Restriction
Orifice/Restriction No.1 3•q¢ 25
No.2 "
No.3 0
No.4
No.5
R I/90
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1 1/2 0 A The boundaries of the sensitive areas dis- One- hundred-year floodplains' e
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Additional sensitive areas that have not surance Rate Maps do not alway!
been mapped may be :present on a devel-. floodplain to the headwaters o
MILE opment proposal site. Where differences
occur between what,is'Illustrated on these
_ maps and the site conditions,the actual pre-
sence or absence on the site of the sensitive
��`Class 1 Issaquahh area - as defined in the Sensitive Area
Ordinance-Is the legal control.
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Class 2(perennial;salmonid a t3
use undetermined) a 14
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130 Andover Park East Seattle,Washington 98188 206/431-7970 Fax/431-7975
I
�
KING COUNTY, W ASHINGTON, SURFACE WATER DESIGN MANUAL
~� IZGURE 3.5.1C 2-YEAR 24-HOUR ISOPLUVIALS
- - •- -
Md
j CCC R LL�v E- • r 'n
tent
Do M
KIM
CV
2-YEAR 24-HOUR PRECIPITATION
..3.4-` ISOPLUVIALS OF 2-YEAR 24-HOUR 35
TOTAL PRECIPITATION IN INCHES
0 1 2 3 4 5 6 7 0 Mlles
cv
1:300,000 ,y 1/90
3.5.1-8
NIMBI
Fla
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
FIGURE 3.5.1E 10-YEAR 24-HOUR ISOPLUVIALS
2.1 ---•— — --- —---— --- ——•——-
22
24
2$ fiq
26
28
29
3.0
3.1
WNW
33
AIA
tw wws
KIM
VA r— ' ' ------- --'
f— 10-YEAR 24-HOUR PRECIPITATION w 4 Y .4
o ,
dP 3.4-o" ISOPLUVIALS OF 10-YEAR 24-HOUR
TOTAL PRECIPITATION IN INCHES
0 1 2 3 4 5 6 7 8 Mlles �fL✓ A 1
3.5.1-10 fJllA�` ..._ 4.
1:300.000 R J 1 0
10i 6i92 41Pacific Engineering Cnmpa* page 1
FORREST CRESTS
9074
BASIN SUMMARY
BASIN ID : A10 NAME : DEVELOPED 10 YR
SBUH METHODOLOGY
TOTAL AREA . . . . . . . 9 .78 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA
PRECIPITATION . . . . : 2 .95 inches AREA . . : 4 .86 Acres
TIME INTERVAL . . . . ; 10 .00 min CN . . . . : 86 .00
TIME OF CONC . . . . . : 5 .00 min IMPERVIOUS AREA
ABSTRACTION COEFF : 0 .20 AREA . . : 4 .92 Acres
CN . . . . : 98 .00
PEAK RATE : 5 .83 cfs VOL : 1 .77 Ac-ft TIME : 470 min
BASIN ID : A100 NAME : DEVELOPED 100 YR
SBUH METHODOLOGY
TOTAL AREA . . . . . . . 9 .78 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA
PRECIPITATION . . . . : ' 3 .9S inches AREA . . : 4 .86 Acres
TIME. INTERVAL . . . . : 10 .00 min CN . . . . : 86 .00
TIME OF CONC . . . . . : 5 .00 min IMPERVIOUS AREA
ABSTRACTION COEFF : 0 .20 AREA . . : 4 .92 Acres
CN . . . . • 98 .00
PEAK RATE : 8 .44 cfs VOL : 2 .54 Ac-ft TIME : 470 min
BASIN ID: A2 NAME : DEVELOPED 2 YR
SBUH METHODOLOGY
TOTAL AREA . . . . . . . : 9 .78 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA,
PRECIPITATION . . . . : 2 .00 inches AREA . . : 4 .86 Acres
TIME ]INTERVAL . . . . : 10 .00 min CN . . . . : 86 .00
TIME OF CONC . . . . . 5 .00 min IMPERVIOUS AREA
ABSTRACTION COEFF : 0 .20 AREA . . : 4 .92 Acres
CN . . . . 98 .00
PEAK RATE : 3 .44 cfs VOL : 1 .07 Ac-ft TIME : 470 min
10/ 6/92 likacific Engineering Company page 2
FORREST CRESTE
9074
BASIN SUMMARY
BASIN ID: a10 NAME : EXISTING 10 YR
SBUH METHODOLOGY
TOTAL AREA . . . . . . . 9 .78 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA
PRECIPITATION . . . . : 2 .95 inches AREA . . : 9 .78 Acres
TIME INTERVAL . . . . : 10 .00 min CN . . . . : 81 .00
TIME OF CONC . . . . . : 32 .23 min IMPERVIOUS AREA
ABSTRACTION COEFF : 0 .20 AREA . . : 0 .00 Acres
CN . . . . • 98 .00
TcReach - Sheet L : 300 .00 ns : 0 .2400 p2yr : 2 .00 s : 0 .O800
TcReach - Shallow L : 370 .00 ks : 3 .00 s:0 .0800
PEAK RATE : 1 .82 cfs VOL : 1 .04 Ac-ft TIME: 480 min
BASIN ID: a100 NAME : EXISTING 100 YR
SBUH METHODOLOGY
TOTAL AREA . . . . . . . : 9 .78 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA
PRECIPITATION . . . . : 3 .95 inches AREA . . : 9 .78 Acres
TIME INTERVAL . . . . : 10 .00 min CN . . . . : 81 .00
TIME OF CONC . . . . . : 32 .23 min IMPERVIOUS AREA
ABSTRACTION COEFF : 0 .20 AREA . . : 0 .00 Acres
CN . . . . : 98 .00
TcReach - Sheet L : 300 .00 ns :0 .2400 p2yr : 2 .00 s :0 .0800
TcReach - Shallow L : 370 .00 ks :3 .00 s: 0 .0800
PEAK RATE : 3 .31 cfs VOL : 1 .69 Ac-ft TIME : 480 min
BASIN ID: a2 NAME : EXISTING 2 YR
SBUH METHODOLOGY
TOTAL AREA . . . . . . . : 9 .78 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA
PRECIPITATION . . . . : 2 .00 inches AREA - : 9 .78 Acres
TIME INTERVAL . . . . : 10 .00 min CN . . . . : 81 .00
TIME OF CONC . . . . . : 32 .23 min IMPERVIOUS AREA
ABSTRACTION COEFF : 0 .20 AREA . . : 0 .00 Acres
CN . . . . : 98 .00
TcReach - Sheet L : 300 .00 ns :0 .2400 p2yr : 2 .00 s :0 .0800
TcReach Shallow L : 370 .00 ks: 3 .00 s: 0 .0800
PEAK RATE : 0 .66 cfs VOL : 0 .49 Ac--ft TIME : 490 min
!10/ 6/92 •Pacific Engineering Company page 3
FORREST CRESTE
9074
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUN{ RATE PEAK HYDRO Area
cfs min . cf-AcFt Acres
1 0 .660 490 21462 of 9 .78
2 1 .820 480 45270 of 9 .78
3 3 .314 480 73826 of 9 .78
C1 3 .441 470 46667 of 9 .78
5 5 .828 470 77126 of 9 .78
6 8 .445 470 110476 of 9 .78
11 0 .660 770 46667 of 9 .78
12 1 .821 530 77126 of 9 .78
13 3 .314 510 110476 of 9 .78
a
10/ S/`2 Vacific Engineering Company page q
FORREST CRESTE
9074
STORAGE STRUCTURE LIST
RECTANGULAR VAULT ID No . V1
Description : VAULT
Length : 130 .00 ft . Width : 35 .00 ft .
10/ 6/92 Vacific Engineering Compano page S
FORREST CRESTE
90%4
DISCHARGE STRUCTURE LIST
MULTIPLE ORIFICE ID No . 01
Description : ORIFICE
Outlet Elev : 400 .00
Elev : 3198 .00 ft Orifice Diameter : 3 .8438 in .
Elev : 402 .80 ft Orifice 2 Diameter : S .9180 in .
Elev : 404 . 10 ft Orifice 3 Diameter : S . 1094 in .
10/ 6/92 4licific Engineering Cnmpanoll page b
FORREST CRESTS
907r
LEVEL POOL TABLE SUMMARY
MATCH INFLOW ST DI <-PEAK-> STORAGE
<--------DESCRIPTION---------> ( cfs ) ( cfs ) id id <-STAGE> id VOL ( cf )
2 YR EX - 2 YR DEV . . . . . . . . . . . 0 .66 3 .44 V1 01 402 .71 11 123
17 .90
10YR EX - 10YR DEV . . . . . . . . . . . 1 .82 5 .83 V1 01 403 .96 12 100
14 .83
100YREX -- 100YR DEV . . . . . . . . . . 3 .31 8 .44 V1 01 405 .46 13 248
51 .33
N
1,0/ 6/92 'Pacific Engineering Company page 7
FORREST CRESTE
'9074
REACH SUMMARY
DITCH REACH ID No . BIO
Ditch Length: 200 .00 ft Ditch Width: 1 .00 ft
Side Slopel : 3 .00 Ditch Slope: 0 .0200 ft/ft
Side Slope2 : 3 .00 Contrib Bas:
Mannings n : 0 .3S00 Dn Invert • 0 .00 ft
Dn W .S . Elev: 0 .0000 Num Steps : 10
Trib Area : 9 .78 Ac . Design Flow : 0 .60 cfs
Depth 0 .65 ft Vel 0 .31 fps
Upstream W .S . Elev : 0 .00 ft .
DITCH REACH ID No . BIOFULL
Ditch Length : 200 .00 ft Ditch Width : 1 .20 ft
Side Slopel : 3 .00 Ditch Slope: 0 .0200 ft/ft
Side Slope2 : 3 .00 Contrib Bas:
Mannings n :0 .0300 Dn Invert • 0 .00 ft
Dn W .S . Elev : 0 .0000 Num Steps : 10
I'rib Area : 9 .78 Ac . Design Flow : 7 .98 cfs
Depth 0 .66 ft Vel 3 .77 fps
Upstream W .S . Elev : 0 .00 ft .
I Ic 0 - - _? -7 0_r_ -79
GINEERING joa -FIS C-Ec,rEL7 -, . 30 -
COMPANY SHEET NQ OF
CIVIL ENGINEERING AND
PLANNING CONSULTANTS CALCULATED SY_(�X -DATE OCIS I C)Z.
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130 Andover Park East Seattle,Washington 98188 206/431-7970 Fox/431-7975
10/ 6/92 IlLcific Engineering Compan4 page 1
FORREST CRESTE -- SOUTH BASIN
9074
BASIN SUMMARY
BASIN ID: A10 NAME : DEVELOPED 10 YR - SOUTH BASIN
SBUH METHODOLOGY
TOTAL AREA . . . . . . . : 1 .08 Acres BASEFLOWS : 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA
PRECIPITATION . . . . 2 .9S inches AREA . . • 0 .SO Acres
TIME INTERVAL . . . . : 10 .00 min CN . . . . : 86 .00
TIME OF CONC . . . . . : 5 .00 min IMPERVIOUS AREA
ABSTRACTION COEFF : 0 .20 AREA . . : 0 .58 Acres
CN . . . . • 98 .00
PEAK RATE : 0 .66 cfs VOL : 0 .20 Ac-ft TIME : 470 min
BASIN ID : A100 NAME : DEVELOPED 100 YR - SOUTH BASIN
SBUH METHODOLOGY
TOTAL AREA . . . . . . . 1 .08 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA
PRECIPITATION . . . . : 3 .95 inches AREA . . : 0 .50 Acres
TIME INTERVAL . . . . : 10 .00 min CN . . . . : 86 .00
TIME OF CONC . . . . . : 5 .00 min IMPERVIOUS AREA
ABSTRACTION COEFF : 0 .20 AREA . . : 0 .S8 Acres
CN . . . . . 98 .00
PEAK RATE : 0 .9S cfs VOL : 0 .28 Ac-ft TIME : 470 min
BASIN ID : A2 NAME : DEVELOPED 2 YR -- SOUTH BASIN
SBUH METHODOLOGY
TOTAL_ AREA . . . . . . . : 1 .08 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA
PRECIPITATION . . . , : 2 .00 inches AREA . . : 0 .50 Acres
TIME INTERVAL . . . . : 10 .00 min CN . . . . : 86 .00
TIME OF CONC . . . . . : 5 .00 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 .20 AREA . . : 0 .58 Acres
CN . . . . : 98 .00
PEAK RATE : 0 .39 cfs VOL : 0 . 12 Ac-ft TIME : 470 min
1-0/ 6/92 Pacific Engineering Company page 2
FORREST CRESTE - SOUTH BASIN
9074
BASIN SUMMARY
BASIN ID: a10 NAME : EXISTING 10 YR -- SOUTH BASIN
SBUH METHODOLOGY
`DOTAL AREA . . . . . . . : 1 .08 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA
PRECIPITATION . . . . : 2 .95 inches AREA . . : 1 .08 Acres
TIME INTERVAL . . . . : 10 .00 min CN . . . . . 81 .00
TIME OF CONC . . . . . : 61 .42 min IMPERVIOUS AREA
ABSTRACTION COEFF : 0 .20 AREA . . : 0 .00 Acres
CN . . . . : 98 .00
TcReach - Sheet L : 310 .00 ns :0 .8000 p2yr : 2 .00 s :0 . 1000
PEAK RATE : 0 . 15 cfs VOL : 0 . 11 Ac-ft TIME : 490 min
BASIN ID : a100 NAME : EXISTING 100YR - SOUTH BASIN
SBUH METHODOLOGY
TOTAL AREA . . . . . . . : 1 .08 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA
PRECIPITATION . . . . : 3 .94 inches AREA . . : 1 .08 Acres
TIME INTERVAL . . . . : 10 .00 min CN . . . . : 81 .00
-TIME OF CONC . . . . . .. 61 .42 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 .20 AREA . . : 0 .00 Acres
CN . . . . 98 .00
TcReach - Sheet L : 310 .00 ns :0 .8000 p2yr : 2 .00 s :0 . 1000
PEAK RATE : 0 .27 cfs VOL: 0 . 19 Ac-~ft TIME : 490 min
BASIN ID : a2 NAME : EXISTING 2YR - SOUTH BASIN
SBUH METHODOLOGY
TOTAL AREA . . . . . . . . 1 .08 Acres BASEFLOWS: 0 .00 cfs
RAINFALL TYPE . . . . : USER1 PERVIOUS AREA
PRECIPITATION . . . . 2 .00 inches AREA . . 1 .08 Acres
TIME INTERVAL . . . . : 10 .00 min CN . . . . . 81 .00
-TIME OF CONC . . . . . : 61 .42 min IMPERVIOUS AREA
ABSTRACTION COEFF : 0 .20 AREA . . : 0 .00 Acres
CN . . . . . 98 .00
TcReach -- Sheet L : 310 .00 ns:0 .8000 p2yr : 2 .00 s : 0 . 1000
PEAK RATE : 0 .OS cfs VOL : 0 .05 Ac-ft TIME :: 520 min
0 i
1,0/ 6/92 Pacific Engineering Company page 3
FORREST CRESTS - SOUTH BASIN
9074
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min . cf-AcFt Acres
1 0 .053 520 2370 of 1 .08
0 . 148 490 4999 of 1 .08
3 0 .270 490 8120 of 1 .08
ZI 0 .391 470 5277 of 1 .08
5 0 .656 470 8663 of 1 .08
6 0 .945 470 12361 of 1 .08
11 0 .053 1010 5274 of 1 .08
12 0 . 148 550 8658 of 1 .08
13 0 .270 540 12355 of 1 .08
15 0 .053 540 2370 of 1 .08
16 0 .053 540 2365 of 1 .08
17 0 .053 520 2370 of 1 .08
• 0
10% 6/92 Pacific Engineering Company page
FORREST CRESTS - SOUTH BASIN
9074
STORAGE STRUCTURE LIST
RECTANGULAR VAULT ID No . V2
Description . SOUTH VAULT
Length : 130 .00 ft . Width : 10 .00 ft .
Pacific Engineering Company page 5
FORREST CRESTS - SOUTH BASIN
9074
DISCHARGE STRUCTURE LIST
MULTIPLE ORIFICE ID No . 02
Description : SOUTH ORIFICE
Outlet Elev= 410 .00
Elev . 408 .00 ft Orifice Diameter : 1 .2451 in .
Elev : 411 .70 ft Orifice 2 Diameter : 2 .4199 in .
Elev . 412 . 10 ft Orifice 3 Diameter : 1 .3008 in .
10/ 6/92 Pacific Engineering Company page 6
FORREST CRESTS -- SOUTH BASIN
9074
LEVEL POOL TABLE SUMMARY
MATCH INFLOW ST DI <-PEAK-> STORAGE
<--------DESCRIPTION---------> ( cfs ) ( cfs ) id id <--STAGE> id VOL ( cf )
EX 2YR DEV 2 YR . . . . . . . . . . . . O .OS 0 .39 V2 02 411 .61 11 20
93 .54
EX 10YR - DEV 10 YR . . . . . . . . . . 0 . 15 0 .66 V2 02 412 .01 12 26
10 .66
EX100YR - DEVIOOYR . . . . . . . . . . . 0 .27 0 .95 V2 02 412 .75 13 35
77 .65
10/ 6/92 Pacific Engineering Company page 7
FORREST CRESTS - SOUTH BASIN
9074
REACH SUMMARY
DITCH REACH ID No . BI02
Ditch Length: 200 .00 ft Ditch Width: 1 .00 ft
Side Slopel : 3 .00 Ditch Slope : 0 .0200 ft/ft
Side Slope2 : 3 .00 Contrib Bas:
Mannings n :0 .3500 Dn Invert - 0 .00 ft
Dn W .S . Elev: 0 .0000 Num Steps : 10
Trib Area : 1 .08 Ac . Design Flow : 0 .05 cfs
Depth 0 .20 ft Vel 0 .16 fps
Upstream W .S . Elev : 0 .00 ft .
DITCH REACH ID No . BI02A
Ditch Length : 180 .00 ft Ditch Width : 1 .00 ft
Side Slopel : 3 .00 Ditch Slope : 0 .0200 ft/ft
Side Slope2 : 3 .00 Contrib Bas:
Mannings n : 0 .3500 Dn Invert - 0 .00 ft
Dn W .S . Elev :0 .0000 . Num Steps 10
Trib Area : 1 .08 Ac . Design Flow : 0 .05 cfs
Depth 0 .20 ft Vel 0 . 16 fps
Upstream W .S . Elev : 0 .00 ft .
DITCH REACH ID No . BI02FULL
Ditch Lengti; : J.E0 .00 ft Ditch Width : 1 .00 ft
Side Slopel : 3 .00 Ditch Slope: 0 .0200 ft/ft
Side Slope2 3 .00 Contrib Bas :
Mannings n : 0 .0300 Dn Invert 0 .00 ft
Dn W .S . Elev : 0 .0000 Num Steps : 10
Trib Area : 1 .08 Ac . Design Flow : 0 .89 cfs
Depth 0 .24 ft Vel 2 . 12 fps
Upstream W .S . Elev : 0 .00 ft .
ci Ic 9
F:'WG NEERING Joe #
COMPANY— SHEET NO. -OF
CIVIL ENGINEERING AND
PLANNING CONSULTANTS CALCULATED BY -DATE
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130 Andover Park East Seattle,Washington 98188 206/431-7970 Fax/431-7975
V . CONVEYANCE SYSTEM ANALYSIS AND DESIGN
VI . SPECIAL REPORTS AND STUDIES
N/A
VII . BASIN AND COMMUNITY PLAN AREA
N/A
VIII . OTHER PERMITS
IX. EROSION/SEDIMENTATION CONTROL DESIGN
h SHEET NO. 11
KING COUNTY AREA, WASHINGTON
(RENTON QUADRANGLE)
+ 1680000 FEET 1220 '30"
to d05 AkF (Joins sheet 5) amc ISSAQUAH I?MI. 10 0'
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X . BOND QUANTITIES WORK SHEET
King County •
Building and Land Development Division BOND QUANTITIES WORKSHEET
COMMERCIAL/MULTIFAMILY GROUP
Page 1 of 2
Date: BALD Project No..
Project Name:
Site Address:
t
i
Fill in those items which pertain to this project and return to the Commercial/Multifamily Group - Site Development
Review Unit.
PUBLIC ROADWAY IMPROVEMENTS PRIVATE ON-SITE IMPROVEMENTS
Unit
Price Unit Quantity Price Quantity Price
A.C.Pavement . . . . . . . . . . $ 8.00 SY �, $ I $
Cement Conc. Curb & Gutter . . . 9.00 LF $ I $
Extruded Asphalt Curb . . . . . 2.50 LF $ I $
Concrete Sidewalk . . . . . . . 9.00 LF $ $
6" pipe . . . . . . . . . . . . 7.50 LF $ $
8" pipe . . . . . . . . . . . . 10.00 LF $ $
12" pipe . . . . . . . . . 15.00 LF $ $
15" pipe . . . . . . . . . . . . 16.00 LF $ $
181, pipe . . . . . . . . . . . . 20.00 LF $ ( $
241, pipe . . . . . . . . . . . . 26.00 LF $ $
36" pipe . . . . . . . . . . . . 30.00 LF $ $
481, pipe . . . . . . . . . . . . 50.00 LF $ $
60" pipe . . . . . . . . . . . . 65.00 LF $ I $
72" p i pe . . . . . . . . . . . . 80.00 LF $ $
Curb Inlet . . . . . . . . . . . 500.00 EA. $ $
CB TYPE I & I-L . . . . . . . . 750.00 EA. $ I $
CB TYPE II - 431, . . . . . . . . 1400.00 EA. $ $
CB TYPE II - 54" . . . . . . . . 2100.00 EA. $ $
CB TYPE II - 72" . . . . . . . . 3400.00 EA. $ $
CB TYPE II - 96" . . . . . . . . 4000.00 EA. $ $
Restrictor/Separator 12" . . . . 450.00 EA. $ I $
Restrictor/Separator 15" . . . . 500.00 EA. $ $
Restrictor/Separator 18" . . . . 600.00 EA. $ I $
Restrictor/Separator 2411 . . . . 750.00 EA. $ I $
Fencing (around pond) . . . . . 10.00 LF $ I $
R i prap . . . . . . . . . . . . . 30.00 CY $ I $
Rockery, Gabion & ecology wall . 7.00 SF $ $
Concrete Retaining Wall . . . . 8.00 SF I $ $
Excavation for Pond . . . . . . 5.00 CY $ I $
infiltration Trench . . . . . . 15.00 LF $ I $
Flow Spreader . . . . . . . . . 15.00 LF $ g
Trench Drain . . . . . . . . . . 15.00 LF $ $
Trash Rack . . . . . . . . . . . 100.00 EA. $ I $ I•
Detention Pipe Riser . . . . . . 400.00 EA. $ $
$ $
$ $
f
SUBTOTAL $ SUBTOTAL $
l t i
1/90
BOND QUANTITIES WORKSHEET
King County Building and Land Development Division
Commercial/Multifamily Group page 2 of 2
t
EROSION/SEDIMENTATION
CONTROL FACILITIES
Unit
i
Price Unit Quantity Price
Silt Fcnce . . . . . . . . . . . S 3.00 LF ;
Seeding/Mulch . . . . . . . . . 3000.00 ACRE ;
Temporary Pond . . . . . . . . . 5.00 CY $
Standpipe . . . . . . . . . . . 200.00 EA. S
CB Interim Protection . . . . . 25.00 EA. S
Quarry Spall/Rip-rap . . . . . . 30.00 CY ;
Rock Construction Entrance . . . 300.00 EA. I S
Pipe ( inch dia.) . . . . . . LF $
SUBTOTAL $
t �
Signature: Telephone No.:
Firm Nam:
i
The following information will be completed by the King County Site Development Review Unit.
PUBLIC ROADWAY IMPROVEMENTS: $
PRIVATE ON-SITE IMPROVEMENTS: $
EROSION/SEDIMENTATION CONTROL $
SUBTOTAL $
20% CONTINGENCY $
TOTAL BOND AMOUNT ;
RIGHT-OF-WAY BOND $
48:BONDSHEE.WPF
11/25/1989
1/90
XI . MAINTENANCE AND OPERATION MANUAL
MAINTENANCE REQUIREMENTS FOR DRAINAGE FACILITIES
PICK UP TRASH AND DEBRIS AROUND PROPERTY ON A DAILY BASIS .
ANY VEGETATION WHICH MAY BE POISONOUS INCLUDING BUT NOT LIMITED TO:
TANSY RAGWORT, POISON OAK, STINGING NETTLES OR DEVILS CLUB SHOULD
BE REMOVED IMMEDIATELY . (COORDINATE REMOVAL WITH SEATTLE/KING
COUNTY HEALTH DEPARTMENT) .
ANY ITEMS SUCH AS OIL, GASOLINE, ETC. , SHOULD BE REMOVED
IMMEDIATELY AS NOT TO HARM PLANTS , ANIMALS OR CAUSE POTENTIAL FIRE
HAZARDS . (COORDINATE REMOVAL WITH SEATTLE/ICING COUNTY HEALTH
DEPARTMENT) .
GRASS SHOULD BE MAINTAINED AS NEEDED, NEVER EXCEEDING 18 INCHES IN
HEIGHT, THEN MOWED TO 2 INCHES . OTHER LANDSCAPE AREAS SHOULD BE
KEPT UP ACCORDINGLY AS NOT TO CAUSE INTERFERENCE TO THE COMPLEX.
ANY RODENT DAMAGE TO DAM OR BERM SHALL BE REPAIRED IMMEDIATELY AND
RODENTS DESTROYED. (COORDINATE WITH SEATTLE/ICING COUNTY HEALTH
DEPARTMENT) .
INSECTS SUCII AS WASPS AND HORNETS SHALL BE DESTROYED OR REMOVED
IMMEDIATELY .
REMOVE TREES .CAUSING INTERFERENCE WITH MAINTENANCE OR COMPLEX
ACCESS .
ANY POND SIDE SLOPES WITH EROSION OVER 2 INCHES DEEP SHALL
IMMEDIATELY BE STABILIZED .
WHEN ACCUMULATED SEDIMENT EXCEEDS 10% OF THE POND DEPTH THE POND
SHALL BE CLEANED OUT TO DESIGNED DIMENSIONS AND EROSION CONTROL
. MEASURES TAKEN IF NEEDED.
ANY DIKE THAT SETTLES 4 INCHES BELOW THE ORIGINAL ELEVATION SHOULD
BE BUILT BACK TO THE ORIGINAL DESIGN ELEVATION.
REPLACE ROCK IN EMERGENCY OVERFLOW/SPILLWAY AS NEEDED TO MAINTAIN
ORIGINAL DESIGN STANDARDS .