Tracts ‘AB’ & ‘C’ Vernal Pool Restoration Project

Tracts ‘AB’ & ‘C’ Vernal Pool Restoration Project

Tracts ‘AB’ and ‘C’ are located along the northern boundary of the Sacramento National Wildlife Refuge.  The tracts’ 755 acres primarily  support natural vernal pools and vernal pool-alkali meadow complexes. Numerous special-status plant species that are associated with these habitats occur there, most of which are included on the California Native Plant Society’s List 1B (rare, threatened, or endangered in California and elsewhere). Tracts ‘AB’ and ‘C’ received substantial runoff from the agricultural fields north of the refuge.  This influx of water altered the natural hydrology of the sensitive native habitat and created conditions that favor seasonal marsh rather than the vernal pool and vernal pool-alkali meadow complex habitats that naturally occur there.  The seasonal marshes that developed were unmanaged, of relatively poor quality, and were currently spreading. The goal of this project was to restore natural hydrology and protect and conserve this unique habitat.

The following is a summary of George F. Cathey’s technical contribution to the project (as an employee of Duck Unlimited, Inc.):

  • Lead investigator for the engineering assessment and Engineer in Responsible Charge and lead designer for all work associated with implementation of the restoration project.
  • Feasibility Study and Engineering Assessment – Investigated feasible alternatives to restore natural hydrology to 755 acres of natural/remnant vernal pools and vernal pool-alkali meadow complexes that were being impacted by off-site agricultural run-off. Conducted a complete topographic survey of the tracts and an inventory of vernal pool features as part of the study using survey grade RTK GPS systems. The feasibility study recommended breaking the project into two phases (Phase I and Phase II) based on the project scope and potential funding sources.
  • Funding Proposals – Collaborated with biological staff to obtain funding for the recommended design alternative, providing cost estimates and drawings/exhibits for both Phase I and Phase II work.
  • Design – Oversaw all Phase I and II design components, which included hydraulic modeling, earth calculations, and water control structure design. Worked closely with USFWS staff through all phases of the design and construction to minimize disturbance to special status species and ongoing operation and maintenance activities on the refuge.
  • Construction Package – Developed the construction package (specifications, drawings, engineer’s opinion of probable cost, and unit price table) for Phase I work and oversaw the development of the Phase II construction package.
  • Provided construction management services for Phase I, including pre-bid and pre-construction meetings, staking and construction oversight and inspection.