The Mason Creek watershed which is located within Washington, Waukesha, and Dodge Counties, is an 8.2-square mile sub-basin within the upper part of the Oconomowoc River watershed. Mason Creek discharges to North Lake along with the Oconomowoc and Little Oconomowoc Rivers. Several lakes (Friess, Loews, Keesus, Beaver, and Pine) also contribute flow to North Lake. Discharge from North Lake flows through Okauchee Lake, Oconomowoc Lake, Fowler Lake, and Lac La Belle before the Oconomowoc River flows into the Rock River. The Mason Creek watershed has been identified as an important contributor of sediment and phosphorus to both the Oconomowoc and Rock Rivers. Mason Creek has been listed as an impaired waterway by the U.S. Environmental Protection Agency (USEPA) and Wisconsin Department of Natural Resources (WDNR). Excessive sediment and nutrient loading to North Lake have led to unnatural conditions such as increased algal blooms, deep water oxygen depletion, and water clarity issues. North Lake has been listed as impaired for high phosphorus loads. A significant amount of the nonpoint source loads of phosphorus and sediment to North Lake were found to be coming from the Mason Creek watershed. This fact, along with low dissolved oxygen, elevated water temperature, and degraded habitat prompted local units of government and organizations to partner with State and Federal agencies to improve the water quality in the Lake and watershed. Although these efforts have had had some success, the water quality in North Lake and Mason Creek continues to be a cause for concern. In response, the North Lake Management District and Tall Pines Conservancy worked with the Southeastern Wisconsin Regional Planning Commission to develop the Mason Creek Watershed Protection Plan in cooperation with the City of Oconomowoc, Towns of Erin and Merton, Washington and Waukesha Counties, the WDNR, USEPA, and the Natural Resources Conservation Service (NRCS). The Mason Creek Watershed Protection Plan provides a framework for communities to work together on a common mission to protect and improve land and water resources and meet the assigned TMDL load and wasteload allocations. The protection plan is designed to be a practical guide for the improvement of water quality within the Mason Creek watershed, addressing the management of land surfaces that drain directly and indirectly to streams and consequently to downstream reaches including North Lake, the Oconomowoc River, the Rock River, and ultimately, the Mississippi River.

The Mason Creek watershed which is located within Washington, Waukesha, and Dodge Counties, is an 8.2-square mile sub-basin within the upper part of the Oconomowoc River watershed. Mason Creek discharges to North Lake along with the Oconomowoc and Little Oconomowoc Rivers. Several lakes (Friess, Loews, Keesus, Beaver, and Pine) also contribute flow to North Lake. Discharge from North Lake flows through Okauchee Lake, Oconomowoc Lake, Fowler Lake, and Lac La Belle before the Oconomowoc River flows into the Rock River. The Mason Creek watershed has been identified as an important contributor of sediment and phosphorus to both the Oconomowoc and Rock Rivers. Mason Creek has been listed as an impaired waterway by the U.S. Environmental Protection Agency (USEPA) and Wisconsin Department of Natural Resources (WDNR). Excessive sediment and nutrient loading to North Lake have led to unnatural conditions such as increased algal blooms, deep water oxygen depletion, and water clarity issues. North Lake has been listed as impaired for high phosphorus loads. A significant amount of the nonpoint source loads of phosphorus and sediment to North Lake were found to be coming from the Mason Creek watershed. This fact, along with low dissolved oxygen, elevated water temperature, and degraded habitat prompted local units of government and organizations to partner with State and Federal agencies to improve the water quality in the Lake and watershed. Although these efforts have had had some success, the water quality in North Lake and Mason Creek continues to be a cause for concern. In response, the North Lake Management District and Tall Pines Conservancy worked with the Southeastern Wisconsin Regional Planning Commission to develop the Mason Creek Watershed Protection Plan in cooperation with the City of Oconomowoc, Towns of Erin and Merton, Washington and Waukesha Counties, the WDNR, USEPA, and the Natural Resources Conservation Service (NRCS). The Mason Creek Watershed Protection Plan provides a framework for communities to work together on a common mission to protect and improve land and water resources and meet the assigned TMDL load and wasteload allocations. The protection plan is designed to be a practical guide for the improvement of water quality within the Mason Creek watershed, addressing the management of land surfaces that drain directly and indirectly to streams and consequently to downstream reaches including North Lake, the Oconomowoc River, the Rock River, and ultimately, the Mississippi River.

The Mason Creek watershed which is located within Washington, Waukesha, and Dodge Counties, is an 8.2-square mile sub-basin within the upper part of the Oconomowoc River watershed. Mason Creek discharges to North Lake along with the Oconomowoc and Little Oconomowoc Rivers. Several lakes (Friess, Loews, Keesus, Beaver, and Pine) also contribute flow to North Lake. Discharge from North Lake flows through Okauchee Lake, Oconomowoc Lake, Fowler Lake, and Lac La Belle before the Oconomowoc River flows into the Rock River. The Mason Creek watershed has been identified as an important contributor of sediment and phosphorus to both the Oconomowoc and Rock Rivers. Mason Creek has been listed as an impaired waterway by the U.S. Environmental Protection Agency (USEPA) and Wisconsin Department of Natural Resources (WDNR). Excessive sediment and nutrient loading to North Lake have led to unnatural conditions such as increased algal blooms, deep water oxygen depletion, and water clarity issues. North Lake has been listed as impaired for high phosphorus loads. A significant amount of the nonpoint source loads of phosphorus and sediment to North Lake were found to be coming from the Mason Creek watershed. This fact, along with low dissolved oxygen, elevated water temperature, and degraded habitat prompted local units of government and organizations to partner with State and Federal agencies to improve the water quality in the Lake and watershed. Although these efforts have had had some success, the water quality in North Lake and Mason Creek continues to be a cause for concern. In response, the North Lake Management District and Tall Pines Conservancy worked with the Southeastern Wisconsin Regional Planning Commission to develop the Mason Creek Watershed Protection Plan in cooperation with the City of Oconomowoc, Towns of Erin and Merton, Washington and Waukesha Counties, the WDNR, USEPA, and the Natural Resources Conservation Service (NRCS). The Mason Creek Watershed Protection Plan provides a framework for communities to work together on a common mission to protect and improve land and water resources and meet the assigned TMDL load and wasteload allocations. The protection plan is designed to be a practical guide for the improvement of water quality within the Mason Creek watershed, addressing the management of land surfaces that drain directly and indirectly to streams and consequently to downstream reaches including North Lake, the Oconomowoc River, the Rock River, and ultimately, the Mississippi River.

The Mason Creek watershed which is located within Washington, Waukesha, and Dodge Counties, is an 8.2-square mile sub-basin within the upper part of the Oconomowoc River watershed. Mason Creek discharges to North Lake along with the Oconomowoc and Little Oconomowoc Rivers. Several lakes (Friess, Loews, Keesus, Beaver, and Pine) also contribute flow to North Lake. Discharge from North Lake flows through Okauchee Lake, Oconomowoc Lake, Fowler Lake, and Lac La Belle before the Oconomowoc River flows into the Rock River. The Mason Creek watershed has been identified as an important contributor of sediment and phosphorus to both the Oconomowoc and Rock Rivers. Mason Creek has been listed as an impaired waterway by the U.S. Environmental Protection Agency (USEPA) and Wisconsin Department of Natural Resources (WDNR). Excessive sediment and nutrient loading to North Lake have led to unnatural conditions such as increased algal blooms, deep water oxygen depletion, and water clarity issues. North Lake has been listed as impaired for high phosphorus loads. A significant amount of the nonpoint source loads of phosphorus and sediment to North Lake were found to be coming from the Mason Creek watershed. This fact, along with low dissolved oxygen, elevated water temperature, and degraded habitat prompted local units of government and organizations to partner with State and Federal agencies to improve the water quality in the Lake and watershed. Although these efforts have had had some success, the water quality in North Lake and Mason Creek continues to be a cause for concern. In response, the North Lake Management District and Tall Pines Conservancy worked with the Southeastern Wisconsin Regional Planning Commission to develop the Mason Creek Watershed Protection Plan in cooperation with the City of Oconomowoc, Towns of Erin and Merton, Washington and Waukesha Counties, the WDNR, USEPA, and the Natural Resources Conservation Service (NRCS). The Mason Creek Watershed Protection Plan provides a framework for communities to work together on a common mission to protect and improve land and water resources and meet the assigned TMDL load and wasteload allocations. The protection plan is designed to be a practical guide for the improvement of water quality within the Mason Creek watershed, addressing the management of land surfaces that drain directly and indirectly to streams and consequently to downstream reaches including North Lake, the Oconomowoc River, the Rock River, and ultimately, the Mississippi River.

Mason Creek Nine Key Plan

The purpose of the project is to monitor and evaluate portions of Mason Creek and its tributaries in Waukesha and Washington Counties. Mason Creek is currently 303d listed for pollutants including total phosphorus and sediment/total suspended solids, with impairments including low DO, degraded habitat and elevated Temperatures and yet it is still listed as a Class I Trout stream. It is also part of the Rock River TMDL area.