HomeMy WebLinkAboutApproved Declaration of CovenantPermit Number:Approved By:Date:
EXHIBIT A - SITE PLAN
B25003568
MAINTENANCE INSTRUCTIONS FOR BASIC DISPERSION
Your property contains an on-site BMP (best management practice) called “basic dispersion,” which
was installed to mitigate the stormwater quantity and quality impacts of some or all of the impervious
surfaces or non-native pervious surfaces on your property.
Basic dispersion is a strategy for utilizing any available capacity of onsite vegetated areas to retain,
absorb, and filter the runoff from developed surfaces. This on-site BMP has two primary components
that must be maintained:
(1) The devices that disperse runoff from the developed surfaces and
(2) The vegetated area over which runoff is dispersed.
Dispersion Devices
The dispersion devices used on your property include the following as indicated on the site
plan (CHECK THE BOX(ES) THAT APPLY):
splash blocks, rock pads, gravel filled trenches, sheet flow.
MAINTENANCE RESTRICTIONS
The size, placement, composition, and downstream flowpaths of these devices as depicted by the site plan and design details must be maintained and may not be changed without written approval from the
City of Renton or through a future development permit from the City of Renton.
INSPECTION FREQUENCY AND MAINTENANCE GUIDELINES
This on-site BMP has two primary components that must be maintained per Appendix A of the City of
Renton’s Surface Water Design Manual:
(1)The devices that disperse runoff from the developed surfaces and
(2)The vegetated flowpath area over which runoff is dispersed.
Maintenance of Dispersion Devices
•Dispersion devices must be inspected annually and after major storm events to identify andrepair any physical defects.
•When native soil is exposed or erosion channels are present, the sources of the erosion orconcentrated flow need to be identified and mitigated.
•Concentrated flow can be mitigated by leveling the edge of the pervious area and/or realigningor replenishing the rocks in the dispersion device, such as in rock pads and gravel filled
trenches.
Maintenance of Vegetated Flowpaths
•The vegetated area over which runoff is dispersed must be maintained in good condition free
of bare spots and obstructions that would concentrate flows.
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EXHIBIT B - OPERATIONS AND MAINTENANCE
RECORDING REQUIREMENT
These basic dispersion on-site BMP maintenance and operation instructions must be recorded as an
attachment to the required declaration of covenant and grant of easement per Requirement 3 of Section C.1.3.4 of the City of Renton Surface Water Design Manual. The intent of these instructions is
to explain to future property owners, the purpose of the BMP and how it must be maintained and operated. These instructions are intended to be a minimum; the City of Renton may require additional instructions based on site-specific conditions. See the City of Renton’s Surface Water Design Manual
website for additional information and updates.
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TYPICAL SPLASH BLOCK TYPICAL 10-FOOT DISPERSION TRENCH CROSS-SECTION
TYPICAL DRIVEWAY APPLICATION OF DISPERSION TRENCH AND ROCK PAD
SIDE VIEWNTS
HOUSE
DOWNSPOUTEXTENSION
SPLASHBLOCK
ROOF DOWNSPOUT
SPLASH BLOCK
100' MIN. VEGETATEDFLOWPATH UNDERFULL DISPERSION,SEE SECTION C.2.1.3
10-foot long dispersion trench
Vegetated Flowpath Segment (NVFS)
Slot drain Diagonal asphalt berm – 2 to 4 inches high
PLAN VIEW OF DRIVEWAY NTS
2-ft x 3-ft x 6-inch crushed rock pad
50-foot separation betweenflowpath segments
Vegetated Flowpath Segment
Edge of undisturbed native vegetation
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