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Maryland / DC


For nearly 60 years, we’ve preserved thousands of acres in the Potomac watershed that ultimately send clean drinking water to our homes in the DC metro region.

By: Dr. Elizabeth Gray

Prince George’s County just narrowly averted an economic crisis in July. More than 100,000 county residents faced up to five days without water, and businesses were preparing to shutter their doors. The Washington Suburban Sanitary Commission, however, prevented the shut-down by diverting water away from a pipe in need of immediate repair.  Here in The Nature Conservancy’s Maryland/DC chapter, we were following the story closely. This incident exemplifies the problems that come with an aging water supply system and highlights the importance of investing in our human-made infrastructure while also safeguarding our region’s source of clean water.

The effective long-term solution is clear: we need to make a combined investment in both our human-made infrastructure and in what we call our “green infrastructure.” By conserving forests, wetlands, rivers, and streams upstream of our growing communities, we can preserve the natural filters that remove harmful contaminants, sediments, and nutrients from the water we drink, and take some pressure off our human-made water supply system.

And that’s particularly important given what we expect for population growth in the area. The addition of more houses, strip malls, and parking lots to serve the projected 1.1 million additional people living in the region by 2040 will contribute to localized flooding and increased pollution of the Chesapeake Bay and our local waters. A 2013 study by the Interstate Commission on the Potomac River Basin looked at climate change and water-demand projections in the Washington metro region. The report found that by 2040, our current water supply system won’t be able to meet the region’s demands during periods of moderate drought without the kind of mandatory water-use restrictions Prince George’s County is currently experiencing, the development of new water storage areas, or both.

The Nature Conservancy is helping to protect our invaluable sources of water. For nearly 60 years, we’ve preserved thousands of acres in the Potomac watershed that ultimately send clean drinking water to our homes in the DC metro region. We’re using scientific techniques to look at how water flows across the land and where we can plant trees most effectively to filter out pollutants. Further afield, on Maryland’s Eastern Shore, we’re working with farmers to reduce pollution flowing to local streams, rivers, and the Bay.

We’re also researching what we can do right here to green the nation’s capital and surrounding cities. If we can convert more of our driveways, parking lots and rooftops to surfaces that absorb water, we’ll reduce the amount of pollution that runs off into our drinking source water. We’re exploring innovative ways to finance this kind of work and will be watching the success of Prince George’s County as it implements a creative plan to pay for the installation of rain gardens and other methods that absorb and filter polluted rainwater running off 2,000 acres of the county.

And we’re interested in adapting a model used in other cities around the world. In this model, instead of funding new water treatment plants, urban residents and businesses help fund the conservation of the upstream forests that provide their water supply. This makes ecological sense and saves people and businesses money. Even for jurisdictions like ours that have already invested in drinking water treatment plants, protecting our watershed prevents pollution and helps protect public health. Watershed conservation also provides other benefits, from clean air to carbon sequestration to wildlife habitat and recreational escapes from city dwelling.

There’s no doubt that many of us take for granted our abundant, affordable and reliable water supply. We turn on the tap and the water flows. Our region has a robust water supply because of decades of coordination by our region’s water utilities and management agencies and because of the foresight and investment of previous generations in protecting important watershed lands. Incidents like that in Prince George’s County however, remind us that water is not an infinite resource, and there may be a time when we will not be able to turn on that tap quite as freely. The strategic decisions we make today about the extent to which we invest in both our human-made and green infrastructure will directly affect the quality and quantity of water available to us, our children and our grandchildren. It is one of the most important investments we can make and we should be willing to do so to ensure that incidents like this are the exception rather than the rule.

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