AMENDED
O-18-015
ORDINANCE
AMENDING THE CITY’S STORMWATER MANAGEMENT ORDINANCES
CITY OF NASHUA
In the Year Two Thousand and Eighteen
The City of Nashua ordains that Part II “General Legislation”, Chapter 190 “Land Use”,
Article XXXI “Stormwater Management”, Section 190-215 “Stormwater management
standards” and Section 190-217 “Operation and maintenance plans” of the Nashua Revised
Ordinances, as amended, be hereby further amended by deleting the struck-through language and
adding the new underlined language as follows:
Ҥ 190-215. Stormwater management standards.
The following stormwater management standards shall be applied to all subdivision and site
plans.
A. Untreated stormwater.
(1) | Nonew stormwater conveyances may discharge untreated stormwater directly to
or cause erosion into wetlands or water bodies.
(2) Rooftop runoff is considered uncontaminated for the purposes of these standards
and therefore does not require treatment.
B. Postdevelopment peak discharge rates.
(1) Stormwater management systems must be designed so that the ten-year twenty-
four-hour postdevelopment peak discharge rate does not exceed the ten-year
twenty-four-hour predevelopment peak discharge rates.
(2) In order to meet this standard, controls must be developed for the two-year, frre-
year_andthe ten-year, and fifty-year twenty-four-hour storm events. The
hundred-year twenty-four-hour storm event must be evaluated to demonstrate that
there will not be increased flooding impacts off site.
