From My Lake to All Lakes: EPA’s National Lake Assessment

By Sarah Lehmann

As I do every year, this summer I spent my vacation on my favorite lake – Rainy Lake.  Rainy is a 228,000-acre lake harboring more than 2,200 islands; it straddles the U.S./Canada border between Minnesota and Ontario.  For me, it’s a place for family and friends to get together and fish, swim, watch wildlife, pick wild blueberries and generally relax without the buzz of cell phones, email, or internet.

This year we had an especially large gathering of family and friends.  We all enjoyed fishing for walleye, northern pike and small mouth bass — and then eating our fresh catch within hours; jumping off “High Rock” into the lake below; seeing bald eagles fly overhead; and hearing the haunting sounds of loons call in the evening.

Unfortunately, according to EPA’s recently published National Lakes Assessment, four out of ten lakes in the U.S. suffer from nutrient pollution.  Excess levels of the nutrients phosphorus and nitrogen from sources such as fertilizer, stormwater runoff, wastewater and even airborne industrial discharges can cause drops in dissolved oxygen and harmful algal blooms. These conditions pose a threat to fish and wildlife, as well as human health. The assessment also finds an association between excess nutrient levels and degraded communities of biological organisms such as the small aquatic insects that are an important part of the lake food chain.

Here at EPA, we are working with our federal, state and local partners to reduce nutrient pollution through a mix of regulatory and voluntary programs.  Just a few of these actions include working with states to identify waters impacted by nutrient pollution and develop plans to restore waters by limiting nutrient inputs; supporting efforts by landowners to adopt stream and shoreline buffers that slow erosion and protect waters from nutrient overload; and providing funding for the construction and upgrading of municipal wastewater facilities.

My grandparents purchased this rustic Rainy Lake getaway for my family more than 40 years ago.  I know that our ability to enjoy this amazing gift – and to pass it down in the same condition to future generations – depends on maintaining the lake’s clean water and healthy, natural shorelines.  The National Lakes Assessment provides information we can use to protect and restore all the Rainy Lakes around the country that are so precious to us all.  To learn more, please visit the National Lakes Assessment website including our innovative interactive dashboard to delve into additional findings and learn more about your conditions in your region.

About the author:  Sarah Lehmann works in the USEPA’s Office of Wetlands, Oceans and Watersheds and is the team leader for the National Aquatic Resource Surveys (NARS).  The recently released National Lakes Assessment  is the latest in the NARS series. 

Editor's Note: The views expressed here are intended to explain EPA policy. They do not change anyone's rights or obligations. You may share this post. However, please do not change the title or the content, or remove EPA’s identity as the author. If you do make substantive changes, please do not attribute the edited title or content to EPA or the author.

EPA's official web site is Some links on this page may redirect users from the EPA website to specific content on a non-EPA, third-party site. In doing so, EPA is directing you only to the specific content referenced at the time of publication, not to any other content that may appear on the same webpage or elsewhere on the third-party site, or be added at a later date.

EPA is providing this link for informational purposes only. EPA cannot attest to the accuracy of non-EPA information provided by any third-party sites or any other linked site. EPA does not endorse any non-government websites, companies, internet applications or any policies or information expressed therein.