As Brentwood grew from a rural outpost to a dense suburb, humans made profound changes to the natural environment. The development of streets and structures significantly altered the methods by which water is disbursed following a rain or snow event. In an undisturbed landscape, most precipitation either infiltrates the soil and collects in underground aquifers or is evaporated into the atmosphere. However, the construction of impervious surfaces, such as concrete or asphalt, substantially increases the quantity of water that instead flows over the land as runoff. Left uncontrolled, runoff can flood roadways, damage foundations, and erode hillsides, while introducing pollutants into local watersheds.

Brentwood manages a system of storm inlets and drainage pipes designed to collect and convey runoff. Under federal and state law, the Borough is required to operate this system in a manner that not only protects community infrastructure but also reduces threats to water quality. As such, the Borough must annually apply for an MS4 (Municipal Separate Storm Sewer System) permit from the Pennsylvania Department of Environmental Protection.

In order to maintain its MS4 permit, Brentwood must demonstrate evidence of compliance with six distinct regulations, which are known as minimum control measures. The aggregate application of these principles has been shown to reduce the amount of oil, fertilizers, trash, and other harmful chemicals and sediments that reach rivers and streams.

1. Public education and outreach. Improving water quality is not just a governmental responsibility. Individual residents and property owners can take steps to abate runoff and contamination. For ideas on how to reduce your stormwater footprint, view the educational material available here. Annual MS4 reports are also available here for public consumption.

2. Public participation and involvement. Our annual Redd-Up Day and Community Clean-Up Day are not just about improving municipal aesthetics. Rather, these events are designed to limit the amount of improperly discarded waste that reaches vital

3. Illicit discharge detection and elimination. Borough personnel actively screen outfall areas for signs of illegal discharge.

4. Construction site runoff control. Active construction sites can contain an array of harmful pollutants. So as to prevent contaminated soil and materials from reaching the watershed, Brentwood requires any developer disturbing more than 1,000 square feet of earth to submit an erosion and sediment control plan.

5. Post-construction runoff control. The actions of property developers can have a major impact on runoff flows. Brentwood encourages the incorporation of green stormwater management devices, such as bio-swales and permeable pavements, into new construction projects.

6. Pollution prevention. While expensive capital construction is sometimes necessary to remediate stormwater, municipalities can also reduce contaminant infiltration through changes in operations. For example, by storing rock salt in an indoor storage facility, the Borough is preventing residual amounts of this corrosive material from being washed into inlets.