California Department of Transportation


Last Updated: Friday, July 6, 2012 9:07 AM

Biological Resources Issues

Staff are currently conducting the following research related to fairy shrimp, vernal pools, and the potential aquatic toxicity of asphaltic materials.

Aquatic Toxicity

Caltrans' Division of Environmental Analysis maintains an on-going interest in the potential for aquatic toxicity impacts of materials used in transportation projects and storm water runoff from transportation facilities. Current research includes the aquatic toxicity of asphaltic products, and the impacts of highway runoff on vernal pool ecosystems. Caltrans is also represented on panel for NCHRP project 25-9 Environmental Impact of Construction and Repair Materials on Surface and Ground Waters. Reports and/or toxicity data derived from this, and past, work are available for asphaltic materials, bridge paints, calcium magnesium acetate and other deicers, herbicide rinse waters, and limited storm water runoff data. A limited aquatic toxicity bioassay capability is maintained.

For further information on aqautic toxicity issues, contact .

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The Beach Lake Mitigation Bank

The California Department of Transporation (Caltrans), in cooperation with the U. S. Army Corps of Engineers, U. S. Environmental Protection Agency, U. S. Fish and Wildlife Service, Federal Highway Administration, and the California Department of Fish and Game has established a wetland and riparian mitigation bank in Sacramento County. The Beach Lake Mitigation Bank (BLMB) is located on a 142 acre Caltrans-owned parcel approximately ten miles south of downtown Sacramento on the west side of Interstate 5. The bank is located in the northern portion of the Stone Lakes National Wildlife Refuge. A total of 67 acres of wetlands and 25 acres of riparian habitat will be established on the parcel for purposes of receiving compensation credit for unavoidable losses to wetland resources from future Caltrans projects. The majority of wetland impacts associated with Caltrans projects are small and linear in nature, therefore, the BLMB will serve as an alternative offsite mitigation site for these small impacts.

The wetland acreages will be established in three shallow excavated basins and will consist of two areas utilized as seasonal wetlands (46 acres total) and one as permanent freshwater marsh (21 acres). Each unit has separate water control structures and can be operated independently of each other. Riprarian vegetation will be established on 25 acres surrounding the wetland units. Construction was completed during the summer of 1995.

The Sacramento-San Joaquin Valley Wetlands Mitigation Bank Act of 1993 (Fish and Game Code Sections 1775-1796) and the Federal Guidance for the Establishment, Use and Operation of Mitigation Banks; Notice (FR Doc. 95-5280) provide guidance on the criteria and standards for the establishment of mitigation banks. In the case of the Beach Lake Mitigation Ban, these items were not issued at the time Agency approvals were being acquired. Therefore, Caltrans and the cooperation Agencies mentioned above developed an Agreement on Mitigation Strategy as the banking instrument of documentation of agency concurrence o the objectives and administration of the Beach Lake Mitigation Bank.

The Agreement was executed in 1994. It outlined the intentions, conditions, and procedures under which Caltrans would establish the bank. All of the Agencies involved are signatory to this Agreement and have approval authority on any proposed mitigation debits from the BLMB. An Initial Study/Environmental Assessment for the project was finalized on July 12, 1993 and circulated for public comment from July 16, 1993 through August 20, 1993. A Negative Declaration was issued on December 8, 1993 and a Findign of No Significant Impact was issued on December 16, 1993. To acquire the water necessary for the wetlands, an Application to Appropriate Water by Permit was filed with the State Water Resources Control Board in 1992. The required permits were obtained prior to construction. Contact for further information.

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Wildflower Demonstration Project

In 1994 a grant from the Federal Highway Administration (FHWA) provided "seed money" to Caltrans to expand the State Office of Landscape Architecture's wildflower project, beginning with the development of a wildflower demonstration site. FHWA asked Caltrans to identify a site on a state highway right-of-way where remnant native wildflowers exist, develop a vegetation management plan to protect these native plants, and promote public awareness of the site as an example of California's unique natural heritage and the need to preserve and protect California's natural resources. This demonstration project is also intended to serve as a model for the rest of the country.

FHWA included a list of recommended criteria to be considered in the selection of a site. The recommendations included: safety--for motorists viewing the site and for workers maintaining the site; location--within the highway right of way, and near an existing preserve or on lands that deserved resource protection because of their biological integrity; and quality--defined by aesthetics, natural beauty and/or regional character.

Over twenty nominations were received from Caltrans personnel, members of the California Native Plant Society, and California Garden Clubs, Inc. A selection committee composed of representatives from Caltrans Office of Landscape Architecture, Division of Environmental Analysis and Maintenance Program, as well as the California Native Plant Society evaluated each site according to the recommended criteria.

The selection committee chose a site in Tehama County along Route 99 between Chico and Red Bluff, adjacent to The Nature Conservancy's Vina Plains Preserve. This site is located in a grassland and vernal pool habitat and features many native plants including some rare species and habitats. This area is famous for spectacular displays of spring wildflowers. Plant life in the pools and swales show concentric rings of color during a spring cycle when the pools fill with rain and then dry slowly through evaporation.

This site is identified with the new highway informational sign and will be managed to ensure the protection of the native plants and unique habitats in the right of way. A public awareness program will help people understand the benefits of preserving California's natural heritage.

We hope that this is only the first of many Caltrans-sponsored wildflower sites throughout the state. If you know of any areas along Caltrans right of way with a spectacular wildflower display please let us know. Contact , Wildflower Program Coordinator, Office of Landscape Architecture.

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