Triangle Rock Vernal Pool and Seasonal Wetland Habitat Enhancement

Sacramento, CA

Triangle Rock Products
August 2002- June 2003

This project is a comprehensive habitat restoration as mitigation for quarry operations east of Sacramento, Ca., designed and monitored by LSA Associates.

Hanford ARC constructed 55 vernal pools among existing pools in a large preserve area, a 3 acre seasonal wetland, planted 800 willow cuttings adjacent to Laguna Creek, and planted and installed irrigation on a 1.5 acre terrace above Laguna Creek. The vernal pool work item required salvaging duff from pools to be disturbed, rough and fine grading new pools, incorporating the shape, depth, and spoils into the surrounding landscape, and spreading the stockpiled duff. The pools have since filled and are blended very well into the landscape, among the existing pools.

The seasonal wetland work item involved excavation of a 3-acre basin adjacent to Laguna Creek, a water quality/detention pond, and several inlet and outlet structures. After performing fine grading, Hanford ARC drill seeded the wetland area with native grasses and forbs. The terrace planting area above Laguna creek consisted of installation of 133 native riparian plants across 1.5 acres, seeding of native grasses and forbs, and installation of an underground irrigation system.

Hanford ARC eradicated a large grove of Ailanthus altissima by cutting and treating the stumps. All seed material was collected from the trees and raked from the ground, resulting very little follow-up treatment required. The duration of the project is from August 2002 to June 2003, including a 60-day establishment period. Hanford ARC is performing detailed and extensive exotic species control, maintenance of plantings, and operation of the irrigation system.