Lake Whatcom - Pollution

Pollution

Lake Whatcom was placed on the Environmental Protection Agency’s 303(d) list for impaired water bodies in 1998, due to low dissolved oxygen (DO) levels. Low Dissolved oxygen are directly related to the amount of phosphorus Lake Whatcom receives. Low DO levels do not directly affect drinking water quality. As required by the 303(d) listing, The Washington State Department of Ecology (DOE) created a computer model to find the Total Maximum Daily Load (TMDL) of phosphorus the lake can receive while maintaining adequate dissolved oxygen levels. In 2008 the DOE estimated that in order to achieve acceptable levels of DO, impervious/run off surfaces need to be returned to pre-1988 levels.

Most of the Phosphorus enters the lake through non point sources. Water runoff from lawns, gardens and streets contain high levels of phosphorus. Aging septic systems in the water can leach phosphorus into the water body. In 2005 fertilizers containing phosphorus were banned to try to reduce the amount of phosphorus entering the lake. The City of Bellingham and Whatcom county have also restricted development activities such as land clearing, from October 1 through May 31 annually to prevent runoff from exposed soil during high precipitation months.

Pet waste also contributes to the pollutant load in the Lake Whatcom watershed. Pet waste contains high levels of fecal coliform which has caused high pollution in 11 of the 22 tributaries running into the lake. A TMDL has been created for these as well.

A 2010-2014 Work Plan for Lake Whatcom was recently approved by the councils of the City of Bellingham, Whatcom County and Water District 10. The Work Plan can be found at http://www.lakewhatcom.whatcomcounty.org/UserFiles/File/WorkPlans/Draft_LW_2010_2014%20Work%20Plan%20Staff%20Final.pdf