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How did this Bay Restoration start and why is MDOT SHA involved?

Under the federal Clean Water Act, states are required to establish water quality standards for all U.S. waters using a multifaceted process.  Water quality standards include designating uses such as fishing, swimming and public water supply; establishing water quality criteria that when met, will sustain the designated uses; identifying waterways that fail to meet water quality criteria and are considered impaired; and developing maximum levels of pollutants that the water body can assimilate and still meet the water quality criteria.  Meeting these maximum levels of pollutants results in restoring the water body.

According to the Environmental Protection Agency (EPA), the Chesapeake Bay is not meeting water quality criteria for dissolved oxygen, Chlorophyll a and water clarity.  It was determined that the pollutants causing these impairments are sediment, phosphorus and nitrogen.  This is documented in the EPA Chesapeake Bay Total Maximum Daily Load for Nitrogen, Phosphorus and Sediment issued December 29, 2010, which is often referred to as the Chesapeake Bay TMDL.

Maryland’s Chesapeake Bay Watershed Implementation Plan (WIP) sets target load reductions within Maryland that seek to return the Bay to compliance with these water quality criteria.  The Maryland Department of Transportation State Highway Administration (MDOT SHA) developed an implementation plan that addresses the MDOT SHA load reduction targets and it is a component of Maryland’s overall WIP.

How is MDOT SHA improving water quality in the Chesapeake Bay Watershed?

MDOT SHA is installing bio-swales and bio-retention ponds, restoring streams and planting thousands of trees to treat storm water running off from highways, driveways and roof surfaces. MDOT SHA’s goal is to achieve a 60 percent reduction in nitrogen, phosphorus and sediment by 2017. MDOT SHA’s program will treat approximately 1,000 more acres of roadway pavement and remove nearly 4,700 pounds of nitrogen and 1,089 pounds of phosphorus from the Chesapeake Bay watershed annually.  The systems in place will also reduce sediment from stream bank erosion from entering water ways.

What is a TMDL?

TMDL (Total Maximum Daily Load), as defined by MDE, is an estimate of the maximum amount of an impairing substance or stressor (pollutant) that a waterbody can assimilate without violating water quality standards.  This total load includes pollutants that come from the end of a pipe (point sources), stormwater runoff and groundwater flow (nonpoint sources), and a "margin of safety" that provides a cushion needed because of uncertainties associated with estimates.  A TMDL also may include an allowance for future increases in pollutant loads due to changes in land use, population growth, and the expansion of business activity.

How do roadways cause water pollution?

Contaminants from vehicles, erosion from roadway construction and maintenance, and roadside litter all have an impact on local waterways.  Stormwater from rain and snow events pick up material existing on roadways (litter, dust, rubber, metal, antifreeze and engine oil, and pesticides and fertilizers) and carry them to local waterways.

How many acres of roadway surfaces is MDOT SHA responsible for?

MDOT SHA is responsible for treating more than 40,000 acres of impervious roadway surfaces.

What strategies are MDOT SHA using to improve water quality?

MDOT SHA is implementing combinations of Best Management Practices (BMPs) to reduce the amount of nitrogen, phosphorus, and sediment from reaching The Chesapeake Bay. MDOT SHA strategy uses structural stormwater controls, non-structural stormwater controls, source controls and land use changes. To learn more about MDOT SHA strategy please see Bay Restoration Strategies.

How do I find out what projects are planned for my area?

There are numerous ongoing projects throughout the state that are occurring within the right-of-way (ROW), including projects conducted by utilities or other companies with permission to be within the ROW. To view SHA Bay Restoration projects, use the interactive map to explore what is going on in your area.

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