The City of Seattle (City) has prepared a multi-species Habitat Conservation Plan (HCP)
to comply with the federal Endangered Species Act (ESA: 16 U.S.C. 1531 et seq.) and to
address a variety of related natural resource issues. The plan will cover the City’s
90,545-acre Cedar River Municipal Watershed and the City’s water supply and hydroelectric
operations on the Cedar River, which discharges into Lake Washington. In general, the City’s
HCP is not an HCP for planned development, but rather it is a set of mitigation and
conservation commitments related to ongoing water supply, hydroelectric power supply, and
watershed management activities.
The HCP is based on a decade of studies and the results of over 5 years of analysis and
negotiations with five state and federal agencies as documented in an Agreement in
Principle, dated March 14, 1997. The Agreement in Principle addresses not only issues under
the Endangered Species Act (ESA) but also related issues under state law and tribal
treaties, and issues with the U.S. Army Corps of Engineers (ACOE). The ACOE manages lake
levels in Lake Washington, and navigational traffic between Lake Washington and Puget Sound,
through operation of the Hiram Chittenden Locks (Ballard Locks) and Lake Washington Ship
Canal.
The City’s commitments regarding these related issues are included in and are part of
this HCP and associated Implementation Agreement (Appendix 1), and the agreements with other
agencies are represented in the related draft Instream Flow Agreement and draft Landsburg
Mitigation Agreement, which are Appendices 27 and 28 of this HCP, respectively. The Instream
Flow Agreement covers minimum and supplemental instream flows, operation of an instream flow
commission, supplementation of minimum flows, and water conservation improvements at the
Ballard Locks. The Landsburg Mitigation Agreement covers mitigation for the blockage to
anadromous fish posed by the Landsburg Diversion Dam, where the City diverts water for
municipal and industrial supply, as well as the effects of the intake structure.
The Instream Flow Agreement and the Landsburg Mitigation Agreement are intended to
resolve issues about river flows and fish passage at Landsburg related to a variety of
interests of the different signatory parties in addition to the ESA.
Although the Muckleshoot Indian Tribe (the Tribe) has not signed any of the agreements
related to the HCP, the City attempted to address many of the issues raised by the Tribe
during negotiations, and the Tribe participated in the development of the proposed instream
flows and mitigation for the Landsburg blockage to fish. The City and Services continue to
seek the Tribe’s agreement on issues related to instream flows and the blockage to fish
passage posed by the City’s Landsburg Diversion Dam.