As more people move into the Chesapeake Bay watershed, more land is cleared for the development of roads, homes and businesses. Residents have expanded out of traditional urban centers and into bigger houses on larger lots, turning forests, farms and other valuable landscapes into subdivisions, shopping centers and parking lots, and impacting the health of our rivers and streams.

How does development affect the Chesapeake Bay?

Development itself does not have to harm the Chesapeake Bay. But the way we develop the land—where we put new roads and buildings and how we construct them—can have a lasting impact on the natural environment.

When low-density residential and commercial areas are built far from existing cities and towns, new infrastructure—schools, roads, shopping centers—is built along with them. Over time, the once-open areas between these new developments and existing cities and towns are filled in. This type of development, called sprawl, chews up forests, farms and shorelines, and degrades land and water habitats.

Forests, wetlands and other vegetated areas can trap water and pollutants, slowing the flow of stormwater runoff. But when urban and suburban development increases, builders often remove these natural buffers to make room for the impervious surfaces (roads, roofs, parking lots, etc.) that allow polluted stormwater to flow freely into local waterways. According to data collected between 2017-2018, 4.87% of the land area within the Chesapeake Bay watershed is impervious surface.

Using more land than we need

As our communities expand out of existing cities and towns, our homes tend to take up more land than we need. According to a report from the U.S. Census Bureau, the median size of a completed single-family house built in 2021 was 2,273 square feet. This is over 50% higher than those built in 1973, even as the average household population has fallen.

Losing forests and farms

Development is one of the biggest threats to forest conservation.

  • Between 1982 and 1997, the watershed lost more than 750,000 acres of forestland to development—a rate of about 100 acres per day. While this rate fell in 2006 to an estimated 70 acres per day, it remains unsustainable.

  • More than 60% of the region’s forests have been divided by roads and subdivisions into fragments. Fragmented forests are less resilient to disturbances and more prone to wildfires, invasive species and other negative influences.

  • According to The State of Chesapeake Forests, more than 35 percent of the region’s private forests are vulnerable to development. Of those vulnerable forest lands, 3.5 million acres are among the most valuable for protecting clean water.

A loss of forests means a loss of valuable habitat that protects clean water and air and supports the region’s economy.

The loss of farmland can also impact the environment: well-managed agricultural lands can restore rivers and streams and provide habitat to insects, birds and mammals. Agriculture is also a large part of the culture, heritage and economy of the watershed.

Data indicating that 70 acres of forest are lost in the watershed every day.

Increasing air and water pollution

Development is inextricably linked to air and water quality. As we build more roads and homes and disturb more parcels of land, we create more pathways that send pollutants into our air and water:

  • People who live outside of urban centers often spend more time traveling in their cars to reach their destinations. This increases congestion on the road and pollution in the air. Vehicle emissions are a source of nitrogen oxides, which account for two-thirds of the airborne nitrogen that ends up in the Bay and contribute to ground-level ozone pollution.

  • Roads, rooftops and parking lots are impervious surfaces: paved or hardened surfaces that do not allow water to pass through. When rain falls onto an impervious surface, it can pick up harmful pollutants before entering storm drains, rivers and streams. A rise in impervious surfaces means a rise in stormwater runoff, which alters natural stream flow and lowers water quality.

  • Development along beaches and shorelines can send excess sediment into the Bay. Man-made, hardened shorelines—those lined with rocks, wood or concrete—can block the formation of wetland habitat and lead to “nearshore erosion,” during which waves erode the shallow area in front of the man-made shore. This increases the amount of sediment suspended in the water.

Changing local heritage and character

Building outside of existing urban centers can change the heritage of existing communities. Development in small towns can impact local farming, fishing and forestry industries, and alter the visual character and “sense of place” that make the region unique.

How is land conserved in the Chesapeake Bay region?

Conserving land and sustaining forests, farms and maritime communities helps protect clean air and water and allows people to experience the natural beauty of our region.

As of 2011, about 55 percent of the Chesapeake Bay watershed was forested and, as of 2019, 9.16 million acres of land—22 percent of the land in the region—had been permanently protected by Chesapeake Bay Program partners.

Land conservation is supported by federal, state, local and privately funded programs. Land is protected through various methods, including conservation easements, purchase of development rights and land donations. Parks, recreational lands and publicly owned lands are also considered preserved land.