HomeMy WebLinkAboutL_Declaration of Covenant_190402_v3B18006356
R-3934
U16006676
Records of King County, Washington, Recording No.
8
Subdivision
REVISION
Received: 04/15/2019 / aalexander
BUILDING DIVISION
PR16000315
B18006356
V3
8
78
EXHIBIT B
Maintenance Details
DRYWELLS FOR LIMITED INFILTRATION (C.2.3.4)
Drywells for Limited Infiltration
Your property contains a stormwater management flow control BMP (best management
practice) called “limited infiltration,” which was installed to mitigate the stormwater
quantity and quality impacts of some or all of the impervious surfaces on your property.
Limited infiltration is a method of soaking runoff from impervious area (such as paved
areas and roofs) into the ground. Infiltration devices, such as gravel filled trenches,
drywells, and ground surface depressions, facilitate this process by putting runoff in
direct contact with the soil and holding the runoff long enough to soak most of it into the
ground. To be successful, the soil condition around the infiltration devise must be able to
soak water into the ground for a reasonable number of years.
The infiltration devices used on your property include the following as indicated on the
flow control BMP site plan: gravel filled trenches, drywells. The size, placement,
and composition of these devices as depicted by the flow control BMP site plan and
design details must be maintained and may not be changed without written approval
either from the City of Renton or through a future development permit from the City of
Renton.
Infiltration devices must be inspected annually and after major storm events to identify
and repair any physical defects. Maintenance and operation of the system should focus
on ensuring the system’s viability by preventing sediment-laden flows from entering the
device. Excessive sedimentation will result in a plugged or non-functioning facility. If the
infiltration device has a catch basin, sediment accumulation must be removed on a yearly
basis or more frequently if necessary. Prolonged ponding around or atop a device may
indicate a plugged facility. If the device becomes plugged, it must be replaced. Keeping
the areas that drain to infiltration devices well swept and clean will enhance the longevity
of these devices. For roofs, frequent cleaning of gutters will reduce sediment loads to
these devices.
PERFORATED PIPE CONNECTION (C.2.11)
Your property contains a stormwater management flow control BMP (best management
practice) called a "perforated pipe connection," which was installed to reduce the
stormwater runoff impacts of some or all of the impervious surface on your property. A
perforated pipe connection is a length of drainage conveyance pipe with holes in the
bottom, designed to "leak" runoff, conveyed by the pipe, into a gravel filled trench where
it can be soaked into the surrounding soil. The connection is intended to provide
opportunity for infiltration of any runoff that is being conveyed from an impervious
surface (usually a roof) to a local drainage system such as a ditch or roadway pipe system.
1. The size and composition of the perforated pipe connection as depicted by the flow
control BMP site plan, Exhibit B, must be maintained and may not be changed
without written approval either from the City of Renton or through a future
development permit from the City of Renton.
2. The soil overtop of the perforated portion of the system must not be compacted or
covered with impervious materials.
PLAN VIEW OF PARCEL
TO STORM DRAINSYSTEMRIGHT-
OF-WAYGENERAL
NOTES:1.INFILTRATION TRENCHES LIMITED TO ROOF RUNOFF FROM SINGLE-FAMILY OR DUPLEX HOMES OR TO
CONTROL BASEMENT FLOODING. CONSULT WA DEPARTMENT OF ECOLOGY REGULATIONS FOR UNDERGROUND
INJECTION CONTROL PROGRAM (UIC) FOR OTHER TYPES OF RUNOFF
MANAGEMENT.2.IMPERVIOUS AREAS LARGER THAN 10,000 SF AND NON-NATIVE PERVIOUS AREAS LARGER THAN 35,000 SF MAY
REQUIRE LARGER PIPE AND SHOULD BE DESIGNED BY A CIVIL
ENGINEER.3.THE PERFORATED PIPE MAY NOT BE PLACED IN A CRITICAL AREA BUFFER OR ON SLOPES STEEPER THAN
25%.4.SEE CONSTRUCTION PLANS FOR SPECIFIC PROJECT
REQUIREMENTS.24"
MIN.18"
MIN.MIN. 1' ABOVE SEASONAL
HIGH GROUNDWATER
TABLE 6"
MIN.1 1/2" - 3/4"
WASHED DRAIN
ROCK NON-WOVEN GEOTEXTILE FOR
SEPARATION ON TOP AND SIDES OF TRENCH PER
WSDOT SPECIFICATIONS SECTION 9-33.2(1) TABLE
3 COMPACTED TOPSOIL OR OTHER CLEAN
FILL 6" MIN.
PVC PERFORATED
PIPE PER ASTM
D1785 10' MIN. LEVEL TRENCH
WITH PERFORATED PIPE, SEE NOTE
1 DOWNSPOUT WITH
CLEANOUT FILTER, SEE
DETAIL ASECTION
A
NOTES:1.TRENCH LENGTH TO BE 10 FEET IN LENGTH FOR EVERY 5,000 SF OF CONTRIBUTING IMPERVIOUS SURFACE, OR 35,000
SF OF NON-NATIVE PERVIOUS SURFACE, OR PORTION
THEREOF.
5'
MIN.
5'
MIN.TO STORM DRAIN
SYSTEM
5'
MIN.
5'
MIN.
A DOWNSPOUT WITH CLEANOUT FILTER, SEE
DETAIL 10' MIN. LEVEL TRENCH
WITH PERFORATED PIPE, SEE NOTE
1 CONFIGURATION ON FLAT
GROUND CONFIGURATION ON SLOPING
GROUND UNDISTURBED NATIVE
SOIL CLEANOUT PER STD. PLAN 226.
00 CLEANOUT
PER STD. PLAN 226.
00 FILTER
SCREEN 2'-5'
TO
GROUND
SOLIDS/
LEAVES TYPICAL
DOWNSPOUT FILTER
DETAIL FOOTING DRAIN
BYPASS CLEANOUT
PER STD. PLAN 226.
00 PERFORATED STUB-
OUT
CONNECTION PUBLIC
WORKS
DEPARTMENT
APPROVED:DATEGregg
Zimmerman Public Works
Administrator UNLESS OTHERWISE NOTED, DRAWING IS NOT TO SCALE (
NTS)STD. PLAN - 263.
40 DocuSign Envelope ID: 6EECF5B6-602A-4E4A-B436-
A317AA638878 9/28/2018 | 9:45 AM