N.H. Code Admin. R. Env-Wq 1508.18

Current through Register No. 25, June 20, 2024

Section Env-Wq 1508.18 - Stormwater Control and Conveyance Practices: Stone Berm Level Spreaders

Stone berm level spreaders shall comply with the following:

(a) The level spreader shall discharge to a vegetated receiving area with the capacity to convey the discharge without erosion;

(b) The receiving area shall:

(1) Have a slope of less than 15 percent; and

(2) Be stable prior to construction of the level spreader;

(c) The level spreader shall:

(1) Be a 6-inch deep trapezoidal trough; and

(2) Have a minimum bottom width of 3 feet;

(d) The level spreader base and top of berm shall be at 0% grade;

(e) The level spreader side slopes and berm side slopes shall be 2:1 or flatter;

(f) The berm shall:

(1) Be at least 18 inches high; and

(2) Have a top width of at least 2 feet; and

(g) The stone used in the berm shall be graded within the following limits:

(1) 100 percent by weight shall pass the 12-inch sieve;

(2) From 84 to 100 percent by weight shall pass the 6-inch sieve;

(3) From 68 to 83 percent by weight shall pass the 3-inch sieve;

(4) From 42 to 55 percent by weight shall pass the 1-inch sieve; and

(5) From 8 to 12 percent by weight shall pass the number 4 sieve;

N.H. Code Admin. R. Env-Wq 1508.18

(See Revision Note #1 at chapter heading for Env-Wq 1500) #9343, eff 1-1-09; (See Revision Note #2 at chapter heading for Env-Wq 1500) amd by #9817-A, eff 12-1-10

Amended by Volume XXXVII Number 32, Filed August 10, 2017, Proposed by #12342, Effective 8/15/2017, Expires 8/15/2027.