A Shoreland Homeowner’s Guide to Stormwater Management
~ protecting your home & environment ~
NH Department of Environmental Services
29 Hazen Drive, Concord, NH 03301 • 603.271.3503 • www.des.nh.gov
Introduction
The Shoreland Water Quality
Protection Act (SWQPA), originally named the Comprehensive
Shoreland Protection Act, which was enacted to help protect the state’s surface waters, includes limits on development that contribute to stormwater runoff. If you are a shoreland homeowner, your property may
What is Stormwater Runoff?
Stormwater runoff describes the flow of rainwater or meltwater from snow or ice over the land’s surface.
On undisturbed sites, much of the stormwater is intercepted by natural ground cover or is absorbed into the ground. Land clearing and development reduces the capacity of the land to absorb rainwater and snowmelt, which leads to more water flowing over the land and into surface waters.
produce stormwater runoff that
As water flows over the land, it picks
directly impacts the quality of
up exposed soil as well as any chemi-
our public waters. However, you
cals, fertilizers or pollutants that are
can reduce or prevent polluted
present. Stormwater carries these polluting substances over impervious surfaces
stormwater runoff. This guide
and through storm drains and drainage ditches. Impervious surfaces are sur-
provides several simple and cost
faces that cannot effectively absorb and infiltrate water. Examples of impervious
effective practices that shore-
surfaces include, but are not limited to, roofs, decks, patios and paved, gravel
land homeowners can install
or crushed stone driveways, parking areas and walkways unless designed to ef-
to address stormwater runoff
fectively absorb and infiltrate water. This flow of stormwater eventually reaches
from roofs, patios, lawns and
a body of water, where the sediments, nutrients and pollutants are deposited.
Polluted stormwater runoff flowing into a storm drain.
driveways. These practices can be used to meet the provisions of the SWQPA. The guide also includes general information about what state environmental permits, if any, are necessary for incorporating these practices.
10 in One!
Please note that this document is actually 10 articles in one: an introductory document and nine guidance sheets, which may be printed out altogether or separately. They are:
Introductory Document, 4 pg.
Dripline Trench, 1 pg.
Drywells, 1 pg.
Infiltration Steps - New, 2 pg.
Infiltration Steps - Retrofit, 1 pg.
How Does Stormwater Runoff Affect Surface Waters?
Alteration of Terrain Permits
The Alteration of Terrain (AoT) permit protects New Hampshire surface waters, drinking water supplies, and groundwater by controlling soil erosion and managing stormwater runoff from developed areas.
This permitting program applies to earth moving operations, such as industrial, commercial, and residential developments as well as sand pits, gravel pits, and rock quarries.
Permits are issued by DES after a technical review of the application, which includes the project plans and support-
As stormwater flows overland as runoff, it picks up and carries a load of sediment, nutrients and pollutants. The faster and more concentrated the flow, the greater the load that stormwater runoff can carry.
Stormwater runoff from developed areas may carry pollutants such as exposed soil, sediment and organic matter; chemicals, fertilizers and herbicides from lawns; animal wastes, cigarette butts and other litter; road salt, chemicals and oil from paved surfaces; and grass clippings, leaves and other yard waste. Stormwater carries these substances through pipes, drains and ditches and eventually into lakes, ponds, rivers and streams. Stormwater slows down after entering a waterbody and deposits the load of nutrients, bacteria, toxic substances, sediment, and other
