Deanne Buckman, Policy Intern

This week is Water Week here in U.S. Water and wastewater professionals from communities across the country will come together to consider and advocate for national policies that advance clean and safe waters for a healthier environment. They will share perspectives, collaborate on solutions, meet with members of Congress and other federal regulators and celebrate past and present achievements. Water Week 2015 will inform and inspire local, state, and national leaders and highlight the importance of the water sector as a means of environmental protection, economic development and job creation.

So why is American Forests a collaborating organization with Water Week? Well, it’s easy to turn on the faucet or guzzle a glass of water without really thinking about where our water comes from, but in fact, clean water comes from forests! America’s forests are actually responsible for providing more than half of the fresh water in this country. Trees catch rainfall, which is filtered by tree roots, other vegetation and the soil before the water reaches the ground. This groundwater then seeps down into aquifers that are tapped by cities for daily use.

As the population continues to grow, more of our nation’s land is taken up by impervious cover, such as pavement, which limits the space available for trees and thereby reduces the groundwater supply in aquifers. These surfaces also increase the amount of stormwater runoff, or rainfall that lands on the impervious surfaces instead of treetops. This water misses out on being filtered by the trees and cannot be absorbed into the ground, and instead flows into streams and lakes carrying with it pollutants such as grease, trash, pesticides and more!

As part of our Urban Forests Case Studies that researched innovative strategies cities have developed to deal with today’s challenges, American Forests looked at Philadelphia, a city with one of the oldest operating sewer systems in the country. Part of the city utilizes a combined sewer system, which carries both sewage and stormwater in one pipe. When rainfall is heavy and stormwater runoff increases, the system reaches capacity and causes a mixture of sewage and stormwater to spill directly into streams and rivers without being filtered. Fortunately, the city has recognized that this system is no longer sustainable and that there is a way in which stormwater can be better managed. The city government has made a commitment to invest in green stormwater infrastructure and reduce reliance on the existing sewer infrastructure.

Together with Philadelphia Parks and Recreation, the Environmental Protection Agency and other groups, the Philadelphia Water Department has developed a plan to turn this commitment into a reality. “Green City, Clean Waters” is a 25-year infrastructure management program aimed at protecting watersheds by managing stormwater runoff. The plan relies on implementing green stormwater infrastructure, a system that takes advantage of the water-plant relationship that naturally occurs in forests. Through the green infrastructure, which will include sidewalk planters, green roofs and a large-scale street tree program, more water will be absorbed into the ground instead of becoming runoff.

Philadelphia’s mayor has promised to make the city the greenest in the nation, and the citizens and government agencies have realized that reducing stormwater runoff through the use of urban trees is an important step to reaching this goal.