Page 137 - Biosystems Engineering

118 Cha pte r T h ree

Forested
Conservation
farming

Rural
Riparian buffer
Urban

Constructed
Swales, wetland
bioretention,
LID
Reservoir
Detention basin
Drinking water
intake

FIGURE 3.8 Simplifi ed schematic of various BMPs on a watershed scale.
(Adapted from U.S. Department of Environmental Protection 2003.)

Twenty Needs Report of the U.S. Environmental Protection Agency
(2002) clearly stresses improved ability of models to evaluate the
effectiveness of BMPs to manage many stressors, including sus-
pended solids and sediments. Varieties of BMPs are available to trap
sediments and control nutrients on a watershed scale, varying from
structural such as wet and dry ponds, vegetative filter strips, riparian
buffers, and wetlands to nonstructural such as conservation tillage
and improved fertilizer and animal-waste management. Figure 3.8
shows a suite of BMPs located in a hypothetical watershed.

3.7.1 Commonly Used BMPs
There are hundreds of different BMPs available with each being more
efficient for certain pollutants and under different conditions. It is
beyond the scope of this book to list all of those BMPs and provide
descriptions on their features, efficiency, how they function, and so
on. Below is a compendium of commonly used BMPs compiled by the
Watershed Science Institute (WSI) of the U.S. Department of Agricul-
ture Natural Resources Conservation Service (USDA-NRCS). Detailed
information on these BMPs such as their purposes, how they func-
tion, limitations, designs, maintenance, and the like can be found at
http://www.wsi.nrcs.usda.gov/products/UrbanBMPs/water.html.