Wading through the sources of lake contamination

Contamination of urban lakes and streams by polycyclic aromatic hydrocarbons (PAHs) is widespread and has been increasing over the last 40 years in the United States.

PAHs are Toxic

These PAHs can be toxic to bottom-dwelling organisms, can cause tumors in fish, and several are believed to cause cancer in humans. 

In this study, researchers examined five sources of PAHs in 40 urban lakes from across the United States, including coal-tar-based pavement sealcoat, coal combustion, oil combustion, vehicle emissions and wood combustion.

Sealcoat Contributes to PAH Contamination

Of the five sources studied, sealcoat was the strongest contributor to PAH contamination in lake sediment. This research can help those trying to reduce pollution levels in the urban environment by providing them with a better understanding of PAH sources. 

This study, "Sources of PAHs to urban lakes in the United States," was conducted by USGS at the Society of Environmental Toxicology and Chemist  

On Lincoln's 200th birthday, Feb. 12, 2009, the new Agriculture Secretary Tom Vilsack "broke pavement" on The People's Garden during a ceremony on the grounds of U.S. Department of Agriculture (USDA) commemorating Lincoln's birthday.

Green for Watershed Protection

Secretary Vilsack declared the stretch of pavement permanently closed and returned back to green, and encouraged other Administration officials and the general public to join in to protect the Chesapeake watershed.

"It is essential for the federal government to lead the way in enhancing and conserving our land and water resources," said Vilsack. "President Obama has expressed his commitment to responsible stewardship of our land, water and other natural resources, and one way of restoring the land to its natural condition is what we are doing here today - "breaking pavement" for The People's Garden."

The dedication comes on the 200th anniversary of the birth of the 16th President of the United States, Abraham Lincoln. Lincoln founded the Department of Agriculture in 1862 and referred to it as "The People's Department" in his last annual message to Congress.

Green for Beneficial Gardening Promotion

Secretary Vilsack announced a goal of creating a community garden at each USDA facility worldwide. The USDA community garden project will include a wide variety of garden activities including Embassy window boxes, tree planting, and field office plots.

The gardens will be designed to promote "going green" concepts, including landscaping and building design to retain water and reduce runoff; roof gardens for energy efficiency; utilizing native plantings and using sound conservation practices.

Green Space for Runoff Reduction

The USDA People's Garden will eliminate 1,250 square feet of unnecessary paved surface at the USDA headquarters and return the landscape to grass. The changes signal a removal of impervious surfaces and improvement in water management that is needed throughout the Chesapeake Bay Watershed.

Demonstration Habitat for Backyard and Green Space Applications

The new garden will add 612 square feet of planted space to showcase conservation practices that all Americans can implement in their own backyards and green spaces.

As a component of the garden, pollinator-friendly plantings will not only provide important habitat for bees and butterflies, but can serve as an educational opportunity to help people understand the vital role pollinators play in our food, forage and all agriculture. The garden plot is adjacent to the site of the USDA Farmer's Market.

Watershed Protection of the Chesapeake Watershed

About 100,000 streams and rivers thread through the Chesapeake's 64,000-square-mile watershed, which is home to almost 17 million people in Virginia, Maryland, Pennsylvania, West Virginia, Delaware, New York and the District of Columbia. The Chesapeake Bay is the largest estuary in North America, with a length of 200 miles and 11,684 miles of tidal shoreline, more than the entire U.S. West Coast.

The Chesapeake Bay supports more than 3,600 species of plants, fish and animals.

Reduce Pollution on Wildlife Habitat, Forests and Water Resources...and Improve Community Natural Resources

USDA leads efforts on public and private lands to help reduce the impact of nutrient and sediment pollution on wildlife habitat, forest lands and water quality, as well as supporting community involvement in managing natural resources, urban green space and land stewardship. For more information about USDA, the People's Garden, the Chesapeake Bay Watershed and other conservation and agriculture related programs available in local communities, visit a USDA Service Center or go to the USDA Web page at www.usda.gov.

Complementary education materials such as the distance-learning project MonarchLIVE and partnerships with schools and the North American Pollinator Protection Campaign which will extend the impact and reach of the USDA garden initiative are available at na.fs.fed.us. Backyard conservation and other materials also can be obtained by dialing 1-888-LANDCARE.

Compared to a patch of lawn, a rain garden allows about 30% more water to soak into the ground!

Rain gardens are NOT solutions for wet areas -- they must have good drainage. Water must soak into the soil within 24 hours to prevent water buildup that becomes a mosquito breeding ground.

• The garden should be at least 10 feet away from buildings.

• The garden should receive full or partial sunlight.

• Avoid areas over septic tanks.

• The garden must include an overflow structure that will allow heavy rains to divert to a natural drainage pattern, not a neighbor's lawn.
• Size the garden to serve the area draining into it, the type of soil on the site, and the depth of the garden.
• Before you dig, remember to call to locate underground utility lines: (1-800-272-1000)
• Choose plants that can tolerate both wet and dry conditions and suited to your garden's sun/shade exposure.

RESOURCES

You'll find a variety of reference materials about rain gardens at this Water Resources Program website ... including: Landscaper Training Program for Rain Gardens - Fact Sheet 29, Cornell University Cooperative Extension, 2007

California trees and shrubs recommended for your rain gardens. A list of California trees and shrubs to brighten and enliven your rain garden.

Low Impact Development with rain gardens. Download a PDF.

Rain Gardens and Bioretention Basins To
Improve Water Quality and Save 30% More Rainwater

Compared to a patch of lawn, a rain garden allows about 30% more water to soak into the ground!

California's water supply is more fragile and seasonal than in most of the country because we are in "the West". Seasonal rains in our desert areas can be severe, and water retention for the rest of the year is dependent on snowpack, water tables and manmade lakes.

When rains come, we need to capture that fresh water for use by the flora and fauna in our communities. Capturing it also prevents runoff from roofs, streets, parking lots and lawns from washing pollutants into streams, rivers, lakes and eventually the ocean. Runoff pollutants can include fertilizers, pesticides, car waste such as oil and fluids, pet waste and its bacteria, eroded soil, road salt, grass clippings and litter. Rain gardens will not remove ALL these pollutants, but they do remove some of them as the water seeps into the ground, which serves as a natural filter.

A beautiful, useful way to capture rainwater runoff is with a "raingarden" that is well designed, well placed and serves as a cache basin that filters and helps the water find its way to the roots of plants...and our watertable.

Read more tips for Rain Garden Landscaping Design