What do you need?

Use the search below to search the site or find your local unit office.

Return to Skip Menu

Main Content

Environmental Quality

Title Summary Date ID Author(s)
A Glossary of Water-Related Terms

The definitions and associated explanations of water-related terms presented here are intended to provide the reader with a working knowledge of terms that apply to Virginia's water resources. The list is designed to assist the user in understanding and interpreting water related information that may come from sources as varied as governmental agencies, environmental groups, or the news media. While terms and definitions are fairly consistent, some terminology presented here could be defined differently to describe water resources issues in other locations.

May 1, 2009 442-758
A Summary of Agricultural Air Quality Perceptions in Virginia Apr 20, 2010 3004-1442
Agricultural Land Application of Biosolids in Virginia: Managing Biosolids for Agricultural Use May 1, 2009 452-303
Agricultural Land Application of Biosolids in Virginia: Production and Characteristics of Biosolids May 1, 2009 452-301
Agricultural Land Application of Biosolids in Virginia: Regulations May 1, 2009 452-302
Agricultural Land Application of Biosolids in Virginia: Risks and Concerns May 1, 2009 452-304
Agricultural Management Practices And Soil Quality: Measuring, assessing, and comparing laboratory and field test kit indicators of soil quality attributes. May 1, 2009 452-400
Backyard Composting

Composting is a degradation process brought about by bacteria and fungus organisms. Large amounts of organic kitchen, garden, lawn, and/or farm refuse can be reduced in a relatively short time to a pile of black, crumbly humus which makes an ideal soil conditioner. Compost added regularly to soil will inevitably benefit the soil. The soil's structure will improve, since humus contains substances which cause aggregation (sticking together) of soil particles. In a clay soil this means that the microscopic individual particles will be clumped together and more air spaces will be opened up between clumps. Without these air spaces the clay particles stick tightly to each other, forming a nearly impenetrable barrier to water and gases. 

Feb 27, 2013 HORT-49P
Best Management Practice Fact Sheet 10: Dry Swale Sep 6, 2013 426-129 (BSE-86P)
Best Management Practice Fact Sheet 11: Wet Swale

A wet swale (WS) is an engineered, best management
practice (BMP) arranged in a straight line that is
designed to reduce stormwater pollution. A WS consists
of a shallow, gently sloping channel with broad,
vegetated, side slopes and slow flows (see figure 1).
Wet swales typically stay wet because the bottom of the
swale is below the water table. This is done to encourage
the growth of wetland vegetation, providing water
quality treatment similar to a natural wetland. This
stormwater treatment practice also functions as part of
the stormwater conveyance system. Wet swales have a
relatively low capital cost; however, maintenance can
be is intensive and expensive when compared to other

Sep 9, 2013 426-130 (BSE-89P)
Best Management Practice Fact Sheet 12: Filtering Practices

A stormwater filtering practice (FP) treats stormwater
runoff by passing it through an engineered filter media
consisting of either sand, gravel, organic matter, and/
or a proprietary manufactured product, collecting it in
an underdrain, and then discharging the effluent to a
stormwater conveyance system. FPs are stormwater
treatment practices that are often obtained from the
marketplace due to unique proprietary technologies
(see figure 1).

Sep 9, 2013 426-131 (BSE-87P)
Best Management Practice Fact Sheet 13: Constructed Wetlands

A constructed wetland (CW) is a low-cost and sustainable,
engineered, best management practice (BMP) designed
to reduce stormwater pollution. Constructed wetlands are
considered to be one of the most reliable stormwater treatment
practices. They are designed to function similarly to
a self-sustaining natural wetland, and should require only
moderate maintenance to function (figure 1).

Sep 9, 2013 426-132 (BSE-91P)
Best Management Practice Fact Sheet 14: Wet Ponds

Wet ponds (WP) are ponds or lakes which provide treatment
and storage of stormwater. The water depth is set
by a structure known as an outlet structure. Wet ponds
are probably the most well-known best management
practice for treatment of stormwater. Because of their
size, they are usually designed to include storage above
the normal pool elevation. This added storage can provide
reductions in downstream flooding and assist in
protecting stream channels. They tend to be large; in
some cases, they can become a passive community
amenity (See Figure 1).

Sep 9, 2013 426-133 (BSE-79P)
Best Management Practice Fact Sheet 15: Extended Detention Ponds

Extended detention ponds (EDs) are dry detention ponds
that provide 12 to 24 hours of runoff storage during peak
runoff events (see figure 1). Releases from the ED ponds
are controlled by an outlet structure. During a storm
event, as the discharge restriction is reached, water backs
up into the ED pond. The pool slows flow velocities and
enables particulate pollutants to settle. Peak flows are
also reduced. ED ponds have the lowest overall pollutant-
removal rate of any stormwater treatment option,
so they are often combined with other upstream, lowimpact
development (LID) practices to better maximize
pollutant-removal rates. Due to their placement at the exit
point of the watershed, ED is often the last opportunity
to treat stormwater before it is discharged to a stream.
Because of its low treatment performance, an ED should
be viewed as the treatment option of last resort.

Sep 9, 2013 426-134 (BSE-82P)
Best Management Practice Fact Sheet 1: Rooftop Disconnection

Rooftop disconnection (RD) is one of the simplest means of reducing stormwater from residential lots. RD takes roof runoff that has been collected in gutters and piped directly to streets, storm drains, and streams and redirects it away from impervious surfaces to landscaped areas (figure 1). Rooftop disconnection is a very sustainable best management practice (BMP) because it controls pollutants in runoff near their source. Redirected runoff from downspouts is infiltrated, filtered, treated, or reused prior to draining into a stormwater conveyance system.

Sep 5, 2013 426-120 (BSE-93P)
Best Management Practice Fact Sheet 2: Sheet Flow to Open Space Sep 6, 2013 426-121 (BSE-83P)
Best Management Practice Fact Sheet 3: Grass Channels Sep 6, 2013 426-122 (BSE-88P)
Best Management Practice Fact Sheet 4: Soil Restoration Sep 6, 2013 426-123 (BSE-80P)
Best Management Practice Fact Sheet 5: Vegetated Roofs Sep 6, 2013 426-124 (BSE-81P)
Best Management Practice Fact Sheet 6: Rainwater Harvesting Sep 6, 2013 426-125 (BSE-90P)
Best Management Practice Fact Sheet 7: Permeable Pavement Sep 6, 2013 426-126 (BSE-84P)
Best Management Practice Fact Sheet 8: Infiltration Practices Mar 2, 2012 426-127 (BSE-85P)
Best Management Practice Fact Sheet 9: Bioretention Sep 6, 2013 426-128(BSE-92P)
Catastrophic Livestock and Poultry Carcass Disposal Nov 19, 2013 ANR-76NP (ANR-90NP)
Closing the Loop: Public-Private Partnerships for On-Farm Composting of Yard Waste May 1, 2009 452-233
Compost: What Is It and What's It To You May 1, 2009 452-231
Composting Your Organic Kitchen Wastes with Worms

Every home kitchen generates food scraps for disposal. Throwing these scraps in the garbage can create odor problems and adds to the volume of waste going to the landfill. Disposing of kitchen scraps in a garbage disposal is convenient, but it adds to the burden of the waste-treatment system and throws away a potentially valuable resource. Furthermore, garbage disposals are not recommended for homes that rely on a septic system for waste disposal. A viable alternative to disposing of food scraps in the landfill or the sewer system is to compost them. The resulting material is a useful addition to gardens and potted plants.

May 1, 2009 442-005
Decentralized Small Community Wastewater Collection Systems Jul 10, 2014 BSE-77P
Denitrification Management Mar 27, 2013 BSE-54P
Denitrifying Bioreaders: An Emerging Best Management Practice to Improve Water Quality Apr 12, 2013 BSE-55P
Distiller's Grains for Dairy Cattle and Potential Environmental Impact

Ethanol is produced when starch in corn grain is fermented. Most other constituents in the grain remain unchanged. The end product of the corn is distiller’s grains or DDGS (distiller’s grains with solubles). The DDGS retain the original fatty acids, protein, and phosphorus. In addition, variability in the grain nutrient content used in the fermentation process and the actual process itself results in a feed with variable nutrient content. Distiller’s grains can be fed either in the wet (less than 25 percent dry matter) or dry (greater than 85 percent dry matter) form. Wet DDGS are difficult to store and must be fed within a few days of production. The wet DDGS can be the most cost-effective, however, if used close to where they are produced.

May 1, 2009 404-135
Effectiveness of Temporary Stream Crossing Closure Techniques Forest Operations Research Highlights Aug 8, 2014 ANR-110NP
Enhanced Efficiency Fertilizer Materials: Nitrogen Stabilizers Aug 22, 2013 CSES-52P
Environmental Best Management Practices for Virginia's Golf Courses Feb 27, 2013 ANR-48NP
Evaluation of Household Water Quality in Albemarle and Fluvanna Counties, Virginia, March-May 2009 Virginia Household Water Quality Program Nov 12, 2010 3010-1502
Evaluation of Household Water Quality in Amherst County, Virginia, June - July 2009, Household Water Quality Program Nov 12, 2010 3010-1503
Evaluation of Household Water Quality in Appomattox and Campbell Counties, Virginia May - June 2009, Virginia Household Water Quality Program Nov 12, 2010 3010-1504
Evaluation of Household Water Quality in Augusta County, Virginia, September - November 2009, Virginia Household Water Quality Program Nov 12, 2010 3010-1505
Evaluation of Household Water Quality in Bath and Highland Counties, Virginia, October-November 2009, Virginia Household water Quality Program Nov 22, 2010 3010-1506
Evaluation of Household Water Quality in Bedford County, Virginia, June-July 2009, Virginia Household Water Quality Program Nov 22, 2010 3010-1507
Evaluation of Household Water Quality in Caroline County, Virginia, January-February 2009, Virginia Household Water Quality Program Nov 22, 2010 3010-1508
Evaluation of Household Water Quality in Culpeper County, Virginia, November-December 2008, Virginia Household Water Quality Program Nov 22, 2010 3010-1509
Evaluation of Household Water Quality in Dinwiddie County, Virginia, February-March 2009, Virginia Household Water Quality Program Nov 22, 2010 3010-1510
Evaluation of Household Water Quality in Greene County, Virginia, April-May 2009, Virginia Household Water Quality Program Nov 23, 2010 3010-1511
Evaluation of Household Water Quality in King George County, Virginia, January-February 2009, Virginia Household Water Quality Program Nov 23, 2010 3010-1512
Evaluation of Household Water Quality in Prince George County, Virginia, January-February 2009, Virginia Household Water Quality Program Nov 24, 2010 3010-1513
Evaluation of Household Water Quality in Rockbridge County, Virginia, September-November 2009, Virginia Household Water Quality Program Nov 29, 2010 3010-1514
Evaluation of Household Water Quality in Rockingham County, Virginia, August-September 2009, Virginia Household Water Quality Program Nov 29, 2010 3010-1515
Fertilizer Applicator Certification Training Apr 12, 2013 ANR-66
Greywater Reuse Apr 30, 2014 BSE-114NP
GroZone Tracker

In-house testing of pH and electrical conductivity (EC) helps to avoid many nutritional problems. Knowing the chemical elements of your irrigation water — and if they vary over time — can help you manage crop quality.

Sep 21, 2016 HORT-227P
Groundwater Quality and the Use of Lawn and Garden Chemicals by Homeowners

The people of Virginia use nearly 400 million gallons of groundwater each day to meet industrial, agricultural, public, and private water demands. One-third of Virginia's citizens rely on groundwater as their primary source of fresh drinking water, and 80 percent of Virginians use groundwater to supply some or all of their daily water needs. Groundwater is an important resource, but it is a hidden one and, therefore, is often forgotten. In fact, until recent incidents of groundwater contamination, little attention was paid to the need to protect Virginia's groundwater.

May 1, 2009 426-059
How Do Stream Buffers Reduce the Offsite Impact of Pollution? Jul 30, 2012 BSE-38P
Impact of Composting on Drug Residues in Large Animal Mortality

Mortalities are inevitable in animal agriculture. For most animal operations in the United States, the average annual mortality is estimated to be between 4.5 and 6 percent of the livestock population. Common methods of mortality disposal include burial, rendering, incineration, and use of a landfill. The availability of options for disposing of mortality, particularly rendering, have changed in recent years, and financially and environmentally sound alternatives are needed. 

Sep 25, 2014 APSC-59P
Implementation: What Happens after the TMDL (Total Maximum Daily Load) is Developed?

A TMDL, or total maximum daily load defines the total pollutant loading a water body can receive and still meet applicable water quality standards. (Italicized terms are defined in the boxes at the bottom of each page.) A TMDL equation is developed from a study that identifies the sources of a particular pollutant in a watershed, the pollutant contribution from each source, and the pollutant reduction required to attain and maintain water quality standards. In TMDL calculations, all identified sources of the particular pollutant are quantified, including both point and nonpoint sources of pollution. Because some TMDL calculations involve assumptions and professional judgment, TMDLs also include a margin of safety to account for uncertainty. (See TMDLs [Total Maximum Daily Loads]: Terms and Definitions, Virginia Cooperative Extension publication 442-550, http://pubs.ext.vt.edu/442-550/.)

May 1, 2009 442-559
Manure Management and Environmental Stewardship Apr 1, 2010 442-309
Mid-Atlantic Composting Directory Jan 6, 2015 452-230 (CSES-99P)
Mitigation of Greenhouse Gas Emissions in Agriculture Apr 2, 2014 BSE-105P
Nitrogen and Sulfur Leaching Potential in Virginia Jun 19, 2015 CSES-125NP
Nutrient Management for Small Farms Oct 8, 2010 442-305
On Farm Mortality Disposal Options for Livestock Producers Jul 31, 2013 2909-1412 (ANR-77NP)
On-Farm Composting - A Guide to Principles, Planning & Operations May 1, 2009 452-232
On-Site Sewage Treatment Alternatives

The purpose of this publication is to describe on-site technologies for treating domestic sewage where conventional systems (septic tank with drainfield) are not an option (U.S. EPA 2002). These technologies are described as alternatives in this publication. Our goal is to provide information that can be used by property owners and residents to initiate action to rectify sewage disposal problems, especially where current wastewater treatment is inadequate. This document is intended to provide information on alternative wastewater treatment options that will help the reader make informed decisions when dealing with oversight agencies and contractors; it is not intended to serve as a stand-alone reference for design or construction.

Sep 21, 2015 448-407 (CSES-116P)
Pest Management for Water Quality

Research has shown that consumers find reading and understanding the label to be the most difficult aspect of applying pesticides. However, an understanding of the label information is essential before work begins. The label printed on or attached to a container of pesticide tells how to use it correctly and warns of any environmental or health safety measures to take. Read the label when you purchase a pesticide and again before mixing or applying it. If you are confused about any part of the label, consult your Extension agent or a representative of the company that makes the product. Many pesticides now list a toll-free number for consumers. The label includes specific information that you should be aware of and learn to understand.

Mar 18, 2015 426-615 (HORT-138P)
Pesticides and Aquatic Animals: A Guide to Reducing Impacts on Aquatic Systems May 1, 2009 420-013
Phosphorus, Agriculture & The Environment

Phosphorus (P) is a naturally occurring element that can be found in the earth's crust, water, and all living organisms. Phosphorus (P) is one of 16 elements that are essential for plant growth. Soils in Virginia are naturally low in phosphorus, and most cropping systems on these soils require supplemental phosphorus to maximize their yield potential.

May 1, 2009 424-029
Poultry and Livestock Manure Storage: Management and Safety Nov 19, 2009 442-308
Rainwater Harvesting Systems May 9, 2014 BSE-116NP
Selecting a Treatment Technology for Manure Management May 11, 2009 442-306
Selection and Location of Poultry and Livestock Manure Storage

If you raise dairy cows, broilers, layers, turkeys, horses, beef cattle, sheep, goats, alpacas, or swine for income or a hobby, you will have to deal with the manure they produce. The amount of manure produced by the birds or animals you keep depends on their type, age, size, and diet.

Nov 19, 2009 442-307
Streamside Livestock Exclusion: A tool for increasing farm income and improving water quality

Did you know that livestock, like humans, prefer a clean water source and are healthier and more productive when they drink clean water? Virginia producers who have restricted or eliminated livestock access to streams and farm ponds and converted to a clean, alternative water source have observed increased livestock productivity, improved water quality, and restored stream banks on their farms. As a consequence, livestock stream exclusion practices are gaining popularity across Virginia. This publication, produced through the cooperation of Virginia Cooperative Extension and the Virginia Department of Conservation and Recreation, describes the findings, experiences, and successes of individual producers who are limiting livestock stream access.

Dec 13, 2012 442-766
TMDLs (Total Maximum Daily Loads) - Terms and Definitions

The definitions of TMDL-related terms presented here are intended to provide the reader with a working knowledge of terms that apply to Virginia's TMDL program. This is the first in a series of Virginia Cooperative Extension publications that deal specifically with TMDLs. The federal Clean Water Act requires States to develop TMDLs for streams, rivers, lakes and estuaries that do not or are not expected to meet applicable water quality standards. This glossary is designed to assist the reader in understanding and interpreting TMDL related information that may come from sources as varied as governmental agencies, environmental groups, consulting firms, or the news media.

May 1, 2009 442-550
TMDLs (Total Maximum Daily Loads) for Bacteria Impairments

A water-quality "impairment" exists if a body of water is unable to support its designated uses. (Italicized terms are defined in the boxes at the bottom of each page.) Virginia's water-quality standards specify that surface waters are either designated for "recreational use" (e.g., swimming, fishing, and boating) or "aquatic life use" (e.g., viable fishing populations). To support the "recreational use," the state sets numeric waterquality criteria for the maximum amount of bacteria in surface waters (Escherichia coli (E. coli)) for fresh water and enterococci for marine waters). When the concentration of bacteria exceeds the state-specified water-quality criteria, the water does not support the designated recreational use and is deemed to have a bacteria or pathogen impairment. E. coli and enterococci bacteria are found in the intestinal tracts and feces of warm-blooded animals, including humans. High counts of these bacteria indicate the presence of fecal contamination in water.

May 1, 2009 442-555
TMDLs (Total Maximum Daily Loads) for Benthic Impairments
"Benthic" refers to the aquatic organisms living in or on the bottom of a body of water. Benthic organisms include crayfish, aquatic snails, clams, leeches, aquatic worms, certain insect larvae and nymphs (e.g., mayflies, dragonflies), and adult aquatic insects (e.g., riffle beetles). Changes in water quality generally result in changes in the types, numbers, or diversity of the benthic community.

In general, a water quality "impairment" exists if a body of water does not support its designated uses. Italicized terms are defined in the boxes at the bottom of each page.

May 1, 2009 442-556
The Nutrient Value of Straw Jun 19, 2015 CSES-126NP
The Soil and Me: A Perspective on Soil Health

Soil is the foundation upon which our natural living world depends; it is otherwise known as the dynamic material that civilization is built on (Lindbo, Kozlowski, and Robinson 2012). Soil serves diverse functions that are critical to the survival of humanity; without the soil, life on earth is inconceivable. It represents the critical zone of the earth where life, water, minerals, and air intersect and interact (fig. 1) because the soil constantly relates with other parts of nature. The soil is considered a living, dynamic resource at the earth’s surface and has been defined as “the unconsolidated mineral or organic material on the immediate surface of the earth that serves as a natural medium for the growth of land plants” (SSSA 2015). The thickness or depth of this surface or layer varies with the type and environment of the soil.

Nov 5, 2015 CSES-132NP
Understanding the Science Behind Riparian Forest Buffers: An Overview May 1, 2009 420-150
Understanding the Science Behind Riparian Forest Buffers: Benefits to Communities and Landowners May 1, 2009 420-153
Understanding the Science Behind Riparian Forest Buffers: Effects on Plant and Animal Communities May 1, 2009 420-152
Understanding the Science Behind Riparian Forest Buffers: Effects on Water Quality May 1, 2009 420-151
Understanding the Science Behind Riparian Forest Buffers: Factors Influencing Adoption May 1, 2009 420-154
Understanding the Science Behind Riparian Forest Buffers: Planning, Establishment, and Maintenance May 1, 2009 420-155
Understanding the Science Behind Riparian Forest Buffers: Resources for Virginia Landowners May 1, 2009 420-156
Urban Stormwater: Terms and Definitions Sep 5, 2013 426-119 (BSE-78P)
Urban Water Quality Management–Residential Stormwater: Put It in Its Place. Decreasing Runoff and Increasing Stormwater Infiltration

Humans and plants depend on an adequate supply of clean water for a number of reasons, from producingfood to sustaining life. The average Virginia resident uses 826 gallons of fresh water daily (Virginia Department of Environmental Quality [VADEQ] 2008). In the Commonwealth alone, there are more than one million households that depend on well water, withdrawing more than 50 billion gallons annually (Virginia Department of Health 2008). For groundwater replenishment, we depend largely on recharge (water moving from the surface to groundwater) from infiltration of precipitation through permeable surfaces in the environment — an important part of the natural water cycle (VADEQ 2010).

Jun 18, 2015 426-046(HORT-160P)
Urban Water-Quality Management: Insect Pests of Water Garden Plants
Aphids are often called plant lice. Several species are troublesome pests on above-water leaves (a), stems, and flower buds of aquatic plants. These sucking insects distort succulent new leaves, causing them to curl, wilt, or turn yellow. Adults are 1/8 inch long and can be winged (c) or wingless (b) with soft pear-shaped bodies with two distinctive cornicles or "tailpipes" protruding from the backs of their abdomens. 
Apr 8, 2015 426-040 (HORT-124P)
Using Reclaimed Water Apr 30, 2014 BSE-115NP
Virginia Citizen’s Guide to Environmental Credit Trading Programs: An Overview

Virginia has implemented several regulatory programs
to improve environmental quality and protect
Virginia’s diverse ecosystems. One approach to help
achieve Virginia’s environmental goals is through
the development of environmental credit trading
programs. These programs can complement pollution
control and environmental protection programs by
providing citizens, businesses, and local governments
with incentives and additional flexibility in achieving
how these requirements are met.

May 4, 2016 ANR-173P
Virginia Landowner’s Guide to the Carbon Market May 28, 2009 442-138
Virginia Master Naturalist Oct 27, 2014 465-300 (ANR-117NP)
Virginia Master Naturalist Program Strategic Planning Report 2015-2020 Apr 9, 2015 ANR-137NP
Virginia Master Naturalist, American Naturalists Jun 19, 2015 465-312(ANR-20NP)
Virginia Tech Pesticide Programs May 11, 2009 vtpp-1
Water Reuse: Using Reclaimed Water for Irrigation

Water reuse can be defined as the use of reclaimed water for a direct beneficial purpose. The use of reclaimed water for irrigation and other purposes has been employed as a water conservation practice in Florida, California, Texas, Arizona, and other states for many years.

May 1, 2009 452-014