Polluted Runoff

Residential stormwater runoff. Photo © 2010 Krista Schlyer/iLCPPolluted runoff in a residential neighborhood flows into a storm drain during a heavy rainfall. Photo © Krista Schlyer/iLCP

The Gray Funnel of the Chesapeake

As water flows off of our streets, parking lots, and building rooftops, it picks up all kinds of pollutants like pet waste, sediment, fertilizers, pesticides, oil, and automotive fluids. If it does not evaporate or soak into the ground—nature's "green filter"—and if untreated or poorly treated, the contaminated runoff adversely affects water quality and aquatic life in local streams, the rivers into which they feed, and ultimately the Chesapeake Bay. As more houses, roads, and shopping centers are built, more of this polluted stormwater or runoff makes its way through gutters and storm drains to the nearest stream.
Graphic showing how the landscape works as a green filter, removing pollution as rainwater sinks into the ground.

Urban and suburban polluted runoff is the only major source of nitrogen pollution in the Bay still growing. Though responsible for greater percentages of pollution, agriculture and sewage treatment plants have made progress. Better stormwater management is an increasingly necessary—but admittedly expensive—proposition for local governments.

As impervious surfaces channel large quantities of rainwater into streams at high velocity, the runoff wreaks havoc. The flow scours stream banks, destabilizes stream contours and alters depths. It muddies drinking water sources and also carries bacteria, making the treatment and use of such water more expensive.

In the Bay's tributaries, eroded material and dirt from the land become suspended in the water, blanketing aquatic habitat. This sediment keeps sunlight from reaching underwater grasses. As these plants die, the animals that rely on them are imperiled.

And it is not only wildlife that is endangered by stormwater pollution. The state of Maryland, for example, cautions people not to swim in waterways for 48 hours after a heavy rain. Stormwater carrying bacteria has resulted in serious illnesses. In urban and suburban areas where ground surfaces have been hardened and the polluted water has no place to go, local streets and basements often flood, causing repeated and costly damage to homes and businesses.

According to the Environmental Protection Agency (EPA), urban and suburban stormwater is the source of about 15 percent of the total nitrogen entering the Bay, and is the only source that is still increasing. In some rivers it makes up an even higher percentage of the problem. It is one of the major reasons that the Bay remains on EPA's "dirty waters" list and is now subject to the Chesapeake Clean Water Blueprint.

Additional information about stormwater management can be found at the following websites:

The Center for Watershed Protection
Low Impact Development Center
Low Impact Development Urban Design Tools

Cover: CBF 2014 Polluted Runoff Report

CBF's investigative report Polluted Runoff: How Investing in Runoff Pollution Control Systems Improves the Chesapeake Bay Region's Ecology, Economy, and Health details the problems created by suburban and urban runoff pollution. And it offers steps that local, state, and federal governments can take to reduce pollution and achieve clean water for local streams, rivers, and the Chesapeake Bay.

Download it today [pdf]

From the CBF Blog


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In the News

11.30.16 - Video Stormwater fees becoming more popular in Pennsylvania as EPA regulations loom

11.07.16 - Rain dance: Different levels of government work for common ground on Bay

11.02.16 - Percolating our way to a cleaner Bay

10.31.16 - Researchers still uncertain of bacteria source in Frederick County waterways

10.28.16 - MDE Approves Counties' Stormwater Financial Plans, Environmentalists Critical

10.26.16 - PA municipalities begin uphill paddle to reach runoff goals, one stroke at a time

10.25.16 - Stormwater cleanup shortcut shouldn't be OK'd

10.22.16 - As stormwater improvement deadlines approach, county seeks flexibility

10.17.16 - Slowing the flow: Fixing flooding with gardens and wetlands

10.17.16 - Flaws alleged in MD localities' stormwater plans

09.18.16 - What's in the midstate water?

09.16.16 - CBF op-ed argues stormwater runoff not just an urban problem

09.14.16 - 'Rain tax' helps fight polluted runoff in county streams

09.08.16 - Ellicott City flood prompts call for nine-month freeze on development

09.01.16 - City nets $315K in river restoration grant

08.31.16 - Bacteria remains concern in small Frederick County waterways

08.30.16 - Harford County has multiple stormwater remediation projects in the works

07.27.16 - A Currency Drop

07.21.16 - Lake pays for the price of runoff

07.12.16 - Kingston, Lehman Townships receive grants for stormwater management

04.07.16 - More boots on the ground needed to inspect erosion at building sites

03.31.16 - Virginia lawmakers OK millions for farm BMPs, sewage plants

03.25.16 - Chesterfield residents speak on budget issues during public hearings

03.23.16 - Most residents at Chesterfield board meeting show support for stormwater fee

03.19.16 - Chesterfield to consider stormwater utility; cost to homes would be $24 annually

03.12.16 - Challenge to stormwater permits denied by Maryland's highest court

03.11.16 - Maryland stormwater permits upheld, rejecting complaints they're not tough enough

03.11.16 - Harford authorized to spend $200,000 for outside lawyers in 'rain tax,' rubblefill cases

01.29.16 - Cheers for regional stormwater plan

01.29.16 - Chesterfield confronts cost of addressing storm water runoff

01.21.16 - Proposed stormwater fee phase-out causes flurry of opposition at Howard County Council hearing

12.31.15 - Street sweeping illustrates nitty-gritty of Chesapeake Bay cleanup program

12.23.15 - Environmentalists threaten to sue to protect yellow perch spawning area

12.18.15 - Embattled Four Seasons development back in court

12.15.15 - Eastern Shore Counties and Towns Unite to Propose Collaborative Actions to Clean Local Waters

11.20.15 - Environmental groups: Bad time to drop 'rain tax' amid high fish kills in Md.

11.18.15 - Confusion and Frustration as Maryland High Court Hears Arguments over Stormwater Permits

11.18.15 - Environmental groups concerned as Baltimore County phases out 'rain tax'

11.17.15 - County Council votes to phase out controversial 'rain tax'

11.16.15 - Baltimore County Council approves phasing out stormwater fee

11.16.15 - Video Rally before unanimous vote repealing rain tax in Baltimore County

11.16.15 - Political storm in Baltimore County over so-called "Rain Tax"

11.02.15 - MD court to hear appeals over stormwater permits for Baltimore, 4 counties

10.26.15 - Bay Foundation questions Baltimore County's move to eliminate 'rain tax'

09.22.15 - Polluted runoff fees help fight local issues

09.21.15 - Talbot County farmer among first in area to adopt two-stage ditch

09.21.15 - CBF Press Release: Farm Bureau Prepares to Ask Supreme Court to Throw Out the Chesapeake Bay Clean Water Blueprint

08.19.15 - Water testing partnership finding high bacteria counts in popular swimming areas

08.13.15 - Green Gardens, Clean Water

06.05.15 - Talbot should fund ditch retrofits

06.05.15 - Talbot launches ditch 'retrofit' experiment

05.18.15 - Environmentalists speak in support of bill to redo city's forest code

04.19.15 - Repeal of 'rain tax' requirement yet to trickle down to most area homeowners

04.17.15 - Faith & Values: Dreaming green brings a rain garden

04.15.15 - Chesapeake Bay's surprising wins

04.15.15 - Talbot should support roadside ditch program

04.14.15 - Still a 'rain tax' by any other name?

04.14.15 - Council opts for reason on stormwater

04.14.15 - Rain tax repeal enacted; lone legislator says bill repeals little

04.13.15 - CBF Press Release Eleventh Hour Passage of Stormwater Bill Caps Remarkable Session for Bay

04.13.15 - CBF Press Statement House of Delegates Strengthens Maryland Stormwater Law

04.13.15 - Talbot County should fund ditch project

04.09.15 - Stormwater fee bill unloved, but deserves backing

04.07.15 - Talbot County Ditches Can Help Save the Bay

04.07.15 - Court faults state oversight of storm-water cleanup efforts

04.02.15 - Miller Gets it Right on 'Rain Tax' Repeal

04.01.15 - Pilot ditch project starts in Royal Oak

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