Section Env-Wq 1507.06 - Peak Runoff Control Requirements(a) The purpose of this section is to address increases in the frequency and magnitude of flooding caused by development.(b) Subject to (d), below, the 10-year, 24-hour post-development peak flow rate shall not exceed the 10-year, 24-hour pre-development peak flow rate for all flows leaving the site.(c) Subject to (d), below, the 50-year, 24-hour post-development peak flow rate shall not exceed the 50-year, 24-hour pre-development peak flow rate for all flows leaving the site.(d) A project area that directly discharges to a stream, waterbody, estuary, or tidal water shall be exempt from (b) and (c), above, if the applicant has provided supporting off-site drainage calculations for the 10-year and 50-year, 24-hour storm in accordance with Env-Wq 1504.09, showing that at a point immediately downstream from the project site the post-development peak flow rate from the site and the off-site contributing area does not exceed the pre-development peak flow rate at that point.(e) The applicant shall provide supporting information in accordance with Env-Wq 1503.09, showing that there is no impact to properties as a result of developing within the 100-year floodplain.N.H. Code Admin. R. Env-Wq 1507.06
(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.