The health of any lake is tied directly to the health of the surrounding landscape. When residential development replaces forested areas, natural filtration processes are replaced with surfaces that funnel runoff into our waterways. One hundred years of residential development has decreased the forested areas around Lake Whatcom and degraded water quality. Healthy soils that support the capture and removal of pollution from runoff are often destroyed or removed during the process of constructing a house, driveway, or lawn. The soil we find below our lawns today cannot absorb and recycle enough nutrients and pollutants, like phosphorus, to protect Lake Whatcom. Data from water sampling and long-term measurements of water quality in Lake Whatcom indicate that our neighborhoods around the lake contribute more than 10 times the amount of phosphorus than the forested area that once stood there.