Close to one-quarter of land in the Chesapeake Bay watershed is devoted to agricultural production. Agriculture is essential to all people: farms provide us with food and fiber, natural areas, and aesthetic and environmental benefits. But agriculture is also the single largest source of nutrient and sediment pollution entering the Bay. While conventional tillage, fertilizers and pesticides can be beneficial to crops, their excessive use can pollute rivers and streams, pushing nutrients and sediment into waterways.
Agricultural land covers close to one-quarter of the Chesapeake Bay watershed. According to 2010 estimates from the U.S. Environmental Protection Agency (EPA), there are more than 87,000 farm operations and 8.5 million acres of cropland here. Farms in the Bay watershed produce more than 50 commodities, including corn, soybeans, wheat, fruits and vegetables. Agriculture is essential to all people: farms provide us with food and fiber, natural areas, and aesthetic and environmental benefits.
Agriculture is the single largest source of nutrient and sediment pollution entering the Chesapeake Bay. According to 2012 estimates from the Bay Program, agriculture contributes 42 percent of the nitrogen, 58 percent of the phosphorous and 58 percent of the sediment entering the Bay. Unfortunately, some agricultural practices—including over-irrigating farmland, over-tilling soil and over-applying fertilizers and pesticides—can push pollution into the Bay and its local waterways.
But well-managed agricultural lands can offer the Bay watershed a number of benefits and services, including sustained crop yields, restored rivers and streams, and valuable insect, bird and animal habitat. When effective agricultural land cover occurs year-round, these systems can store carbon, minimize soil erosion and reduce the watershed’s vulnerability to flooding and the effects of climate change.
Irrigation brings water to land. Through the use of hoses, sprinklers or other watering methods, irrigation can ensure consistent crop production in a range of weather conditions. Fruits, vegetables, grains and horticultural plants are the most commonly irrigated crops in the Bay watershed.
Poor irrigation practices, including the over-watering of crops, can promote erosion and push pollution into rivers and streams:
To prepare a field for planting, a number of farmers practice “conventional tillage,” turning the earth over with a plow. While tillage can loosen the soil and promote crop growth, it can also damage soil structure:
Livestock manure and poultry litter are often applied to cropland as a form of fertilizer, providing crops with the nutrients needed to grow. But when more manure is applied to the land than a crop can absorb, or when large amounts of manure are improperly stored, the nutrients and bacteria that manure contains can:
According to 2010 estimates from the EPA, manure accounts for 19 percent of the nitrogen and 26 percent of the phosphorous entering the Bay. These excess nutrients can fuel the growth of algae blooms that block sunlight from reaching underwater grasses and, during decomposition, rob the water of oxygen that plants and animals need to survive.
Like manure, chemical fertilizers can provide crops with the nutrients needed to grow. But when more fertilizer is applied to the land than a crop can absorb, these nutrients can:
According to 2010 estimates from the EPA, chemical fertilizers account for 17 percent of the nitrogen and 19 percent of the phosphorous entering the Bay. These excess nutrients can fuel the growth of algae blooms that block sunlight from reaching underwater grasses and, during decomposition, rob the water of oxygen that plants and animals need to survive.
Chemical pesticides can protect crops from weeds and insects. Some pesticides target just one or a few species, while others are considered “broad-spectrum” and target a group of similar species. Like livestock manure and chemical fertilizers, when pesticides are applied in excess, they can:
According to a 2012 report from the EPA, U.S. Geological Survey (USGS) and U.S. Fish and Wildlife Service, pesticides are frequently present in our streams and groundwater. While pesticide concentrations in local waterways are seldom high enough to harm human health, pesticide concentrations in a number of streams can impact aquatic and fish-eating wildlife. Scientific studies have discovered potential links between pesticide exposure and:
Bay Program partners are working with farmers across the watershed to curb agricultural runoff. Conservation practices—often called “best management practices” or “BMPs”—can be implemented on area farms, and watershed states are counting on the expanded use of these practices to help them meet the goals set forth in the Chesapeake Bay “pollution diet,” or Total Maximum Daily Load (TMDL).
Best management practices are tools that farmers can use to reduce agricultural runoff into rivers, streams and the Chesapeake Bay. These tools can reduce a farm’s operational costs and improve a farm’s production. Some best management practices are voluntary or incentive-based, while others—like nutrient management planning for all agricultural operations in Maryland—are mandatory.
Conservation tillage leaves one-third or more of a farm field covered with crop residue or vegetation throughout the year. When tillage is reduced and soil is left undisturbed, a field is less prone to erosion. Continuous no-till and minimum-till farming are two forms of conservation tillage.
Cover crops are grown to provide soil cover and prevent erosion. Cover crops can be annual, biennial or perennial plants grown in a single or mixed stand during all or part of the year, including the non-growing season. Common cover crops include legumes (like cowpeas or clover), forage radish and cereal grains (like wheat, rye or barley).
Planting cover crops uses living plants to fill in bare soil in a field. This can occur when a main crop has been harvested, when there is a niche in a season’s crop rotation or when there is a need to interplant a cover crop with a cash crop. Cover crops can:
Grasses, trees and shrubs planted along the edges of farm fields and along rivers and streams can reduce the amount of pollutants flowing from the land into local waterways. These “buffers” can slow and absorb polluted runoff, stabilize stream banks, curb erosion and serve as habitat for wildlife.
Streamside fences exclude livestock from local waterways. Livestock exclusion fencing can reduce the amount of nutrients and pathogens entering the water, prevent stream bank damage and erosion, and improve animal health. Fences can be woven wire or electric, and permanent or moveable.
A nutrient management plan is a written, site-specific plan that reduces nutrient pollution while maintaining crop production and, in some cases, increasing farm profits. By developing a “nutrient budget” for a farm and applying nutrients at the right time, with the right methods, a farmer can limit the amount of nutrients available to run off his land and into local waterways. While all farms will contribute some nutrients to the surrounding environment, those operating under nutrient management plans should contribute fewer nutrients than those farms that are not.
Most nutrient management plans focus on nitrogen and phosphorous and contain:
According to 2010 estimates from the EPA, livestock manure and poultry litter account for almost half of the nutrients entering the Bay. The states in the Bay watershed have committed to reducing this nutrient load by working with farmers to:
The Bay Program’s 2005 Manure Management Strategy identified four opportunities to better manage manure-related nutrient loads in the watershed:
For Chesapeake Bay restoration to be a success, we all must do our part. Our everyday actions can have a big impact on the Bay. By making simple changes in our lives, each one of us can take part in restoring the Bay and its rivers for future generations to enjoy.
To support agriculture in the Bay watershed, consider purchasing products from a local farm. Buying local can reduce the pollution associated with transporting goods over long distances and the packaging needed to transport or store fresh produce. A number of area farms have even become involved in “agritourism,” which invites visitors onto farms to learn about local land and agriculture.
Learn more about farms across the watershed:
Landowner has created a safe haven for waterfowl on Maryland’s Eastern Shore.
Case studies show best management practices have lowered pollution in the Chesapeake Bay.
Bay Program partners work to streamline the conservation reporting process.
Manure spills could pose threats to human health and the environment.
This father and son duo has implemented best management practices on their farm.
From July 2012 to June 2013, about 229 miles of forest buffers were planted along the Bay watershed’s streams and rivers. A total of 7,994 miles have been planted watershed-wide since 1996*.
*Prior to 2010, the Chesapeake Bay Program tracked riparian forest buffer planting in Maryland, Pennsylvania and Virginia. In 2010, CBP began including planting data from New York, West Virginia and Delaware
Computer simulations of pollution controls implemented between July 2009 and June 2013, calibrated using monitoring data, indicate that nitrogen loads to the Bay would have decreased 20.28 million pounds to 262.38 million*.
Computer simulations of pollution controls implemented between July 2009 and June 2013, calibrated using monitoring data, indicate that phosphorus loads to the Bay would have decreased 2.04 million pounds to 17.19 million*.
Computer simulations of pollution controls implemented between July 2009 and June 2013, calibrated using monitoring data, indicate that sediment loads to the Bay would have decreased 497 million pounds to 8,178 million*.
Publication date: October 22, 2006 | Type of document: Policy Memorandum
The Chesapeake Bay jurisdictions and the Chesapeake Bay commission, respectfully convey this policy agreement to our colleagues in the states and U.S. Congress to stress the critical importance of enhancing support for agricultural…
Publication date: October 22, 2006 | Type of document: Policy Memorandum
Agriculture is a primary economic sector in the region containing 3.2 percent of the nation's farm acreage, yet producing 5.7 percent of the nation's agricultural receipts and contributing 13 percent of region's Gross Domestic Product.…
Publication date: March 07, 2006 | Type of document: MOU/MOA | Download: Electronic Version
This resolution urges the Secretary of Agriculture to make the Chesapeake Bay Watershed a priority objective by heightening coordination efforts with other Federal departments and agencies in order to leverage resources available from…
Publication date: January 10, 2005 | Type of document: Directive | Download: Electronic Version
Agriculture is a significant source of nutrients entering the Chesapeake Bay, with animal manure and poultry litter contributing about half of the agricultural nutrient load. As animal operations become more concentrated and the acreage of…
Publication date: February 01, 2004 | Type of document: Report | Download: Electronic Version
Available in digital format and hardcopy. The Scientific and Technical Advisory Committee (STAC), in cooperation with the USDA and the Mid-Atlantic Water Quality Program, convened a forum on innovation in agricultural conservation in May…
Publication date: October 14, 1994 | Type of document: Directive | Download: Electronic Version
In 1992, recognizing the significant role that agriculture plays in the Bay's restoration, the Executive Council launched the Agricultural Nonpoint Source Initiative to develop strategies for the agricultural community to reach their…
Publication date: December 27, 1993 | Type of document: Directive | Download: Electronic Version
Overview of commitments in the Chesapeake Bay Program to restore and protect the ecological integrity, productivity and beneficial uses of the Chesapeake Bay. Signatories include the states of Maryland, Virginia, Pennsylvania, the District…
Publication date: December 27, 1988 | Type of document: MOU/MOA | Download: Electronic Version
This document sharpens the focus of the EPA and the USDA to carry out activities to help Chesapeake Bay Program partners meet their nutrient reduction goals. EPA and USDA commit to using their complementary authorities and programs to work…
Publication date: August 01, 1987 | Type of document: Report | Download: Electronic Version
This is a report on vegetative filter strips for agricultural runoff treatment
Publication date: | Type of document: | Download: Electronic Version
New Insights: Science-based evidence of water quality improvements, challenges and opportunities in the Chesapeake compiles data collected and analyzed by Chesapeake Bay Program partners, including the University of Maryland Center for…