giant reed (Arundo donax) on the deposited sediment. Year 2000 monitoring is scheduled to be conducted on a biennial basis, and the inlet remains blocked, precluding flows from entering the diversion channel.

Introduction

The California Department of Transportation applied for a Department of the Army permit in 1991 to construct State Route 85, a new 18-mile-long 6-lane freeway in San Jose, California. The freeway was designed to link two existing highway corridors, Interstate 280 to the north and U.S. 101 to the south. The construction of State Route 85 resulted in impacts to nine creeks regulated by the Corps pursuant to Section 404 of the CWA. The impacts included construction of bridges over the creeks, construction of storm drain outfalls, realignment of creek channels, installation of hardscape erosion control measures such as rip rap and channel lining, placing fill into the creeks to facilitate widening, culverting flows beneath new sections of road, and installation of flood control facilities such as berms, flood walls, and check dams. The overall project resulted in the placement of approximately 7,600 yd3 of fill within Corps jurisdiction and impacted a total of 9 ac of riparian habitat.

Coyote Creek Mitigation

The Coyote Creek mitigation site is as an off-site mitigation area. It was designed to provide riparian woodland habitat common to California 's Santa Clara Valley, as partial replacement for riparian habitat impacts on nine creeks along the proposed State Route 85 corridor. The Coyote Creek mitigation site is located near U.S. 101 in San Jose, California.

The mitigation project required extensive reworking of the site's topography and hydrology and installation and establishment of large numbers of native riparian plant species. The mitigation site was designed to provide 24.4 ac of riparian habitat adjacent to Coyote Creek. Monitoring for the project was designed to assess the development of riparian habitat from the time of grading and plant installation until the project met or exceeded all success criteria or by mutual agreement between the California Department of Transportation and resource agencies (H.T.Harvey and Associates 1992).

In 1993, the mitigation site was graded and soil removed (approximately 10 to 15 ft deep) in an effort to bring the final grade closer to the groundwater table. In addition, a meandering 2,300-ft-long, 9-ft-wide, 2-ft-deep channel was constructed through the center of the site (USACOE 1991, Public Notice 18998S92). The channel was designed to carry water



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