HomeMy WebLinkAbout224.001.THIS TRENCH SHALL BE CONSTRUCTED SO AS TO PREVENT POINT DISCHARGE AND/OR EROSION.
2.TRENCHES MAY BE PLACED NO CLOSER THAN 50 FEET TO ONE ANOTHER, 10 FEET MINIMUM TO ANY BUILDING
(100 FEET ALONG FLOWLINE).
3.TRENCH AND GRADE BOARD MUST BE LEVEL. ALIGN TO FOLLOW CONTOURS OF SITE.
4.SUPPORT POST SPACING AS REQUIRED BY SOIL CONDITIONS TO ENSURE GRADE BOARD REMAINS LEVEL.
5.15% MAX UNLESS OTHERWISE EVALUATED AND APPROVED, SEE SECTION C.2.1.1.
6.GRADE BOARD AND SUPPORT POST TO BE UNTREATED CEDAR OR RECYCLED PLASTIC. SPACE SUPPORT POSTS
EVERY 10 FEET MINIMUM.
7.GEOTEXTILE TO BE NON-WOVEN TYPE FOR SEPARATION PER WSDOT 9-33.2(1).
NOTES:
INFLUENT PIPE (MAX DESIGN
FLOW <0.5 CFS PER TRENCH)
FLOW TO SECOND
DISPERSAL TRENCH
IF NECESSARY
FLOW TO OTHER
BRANCHING CB'S
AS NECESSARY
12"
MIN.
6" MIN.
12"
MIN.
50'
MAX.
NOTCHED GRADE BOARD,
2"x2" NOTCHES, 18" O.C.
2" GRADE BOARD
NOTCHES (TYP.)18" O.C.
2" (TYP.)
6" MIN. PERFORATED PIPE LAID FLAT/LEVEL
3/4" -1 1/2" WASHED DRAIN ROCK OR GRAVEL BACKFILL FOR
DRYWELLS PER WSDOT STD. SPECIFICATION SECTION 9-03.12(5)
4"x4" SUPPORT POST, SEE NOTE 6
SECTION A
6" MIN.
12" MIN.
36" MAX.
WRAP TRENCH SIDES WITH
GEOTEXTILE (LEAVE TOP AND
BOTTOM EXPOSED), SEE NOTE 7
GALVANIZED BOLT (TYP.)
2"x12" GRADE BOARD,
SEE NOTE 6
NOTCH DETAIL
PLAN
A
15% MAX, SEE
NOTE 5
15% M
A
X
,
S
E
E
NOTE 5
TYPE 1 CB WITH
SOLID COVER
TYPE 1 CATCH BASIN
(CB) WITH SOLID COVER
CAPPED CLEANOUT
WYE FROM PIPE
END CAP OR PLUG
EXPOSED ROCK, DO NOT FILL
50-FOOT DISPERSION TRENCH WITH
NOTCHED BOARD
STD. PLAN - 224.00
PUBLIC WORKS
DEPARTMENT
APPROVED:
DATEMartin Pastucha
Public Works Administrator
UNLESS OTHERWISE NOTED, DRAWING IS NOT TO SCALE (NTS)
DocuSign Envelope ID: 3B1B34D3-7E0A-476C-ADB3-4329FFE0C108
8/13/2020 | 8:48 AM PDT