Expanding Wetland Habitats
The Conaway Preservation Group, in conjunction with Reclamation District 108, is conducting a feasibility study to evaluate expanding wetland and riparian functions of the Tule Canal on Conaway Ranch.
Alternative solutions will be considered, and a preferred alternative selected for subsequent design, permitting, funding, and construction. The Tule Canal is connected to the Sacramento River system and functions as a water supply and agricultural drainage channel, in addition to harboring significant riparian habitat.
The current enhancement opportunity is to expand the wetland area and functions within a 299 acre corridor that includes reforming 28 acres of canal, enhancing 121 acres of riparian habitat, and creating 150 acres of wetland and riparian habitats.
The result would be a substantial benefit to aquatic and terrestrial species of concern, with limited impacts to ranch operations and no loss of offsite water supply and drainage functions.
Existing riparian communities would be enhanced with the addition of bench-step wetland and riparian habitats that would be periodically inundated under a range of flows in the canal, as shown in the figures to the right and below.
The Tule Canal Enhancement Project would take advantage of existing drainage flows in the Tule Canal and more frequent inflows expected as a result of the Yolo Bypass Salmonid Habitat Restoration and Fish Passage Project (Big Notch).
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and Tule Canal Enhancement
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Feasibility Study Goals
The proposed feasibility study is for the Tule Canal Enhancement component of a larger vision at Conaway Ranch that includes salmonid floodplain reconnection with Fish Rearing and Fish Food Subsidy components, as shown to the left.
The two other components envision reconnecting about 3470 acres of Conaway Ranch to the Sacramento River for salmonid rearing and feeding during high flows, and an additional 2,800 acres that could be flooded to provide food subsidy for anadromous and other fish.
Feasibility studies for these two other components will be pursued as funding becomes available. Enhancement options will be designed in a way to coordinate with future plans which may be pursued outside the canal.
The goal of the Tule Canal Enhancement Project is to modify the existing Tule Canal on the Conaway Ranch property to function as an enhanced permanent and seasonal riparian wetland feature, while retaining drainage and water supply functions.
The Project will benefit fall-run, spring-run, and winter-run Chinook salmon as well as Steelhead trout by improving in-channel and floodplain rearing opportunities along the Tule Canal corridor.
The Project will also benefit aquatic, terrestrial, and amphibian species, including threatened and endangered species such as Giant Garter Snake, Western Pond Turtle, Yellow Billed Cuckoo, Swainson’s Hawk, and Tricolored Blackbird. All would benefit from expanded wetland and riparian habitats providing nesting and foraging habitat for bird species, seasonal salmon floodplain rearing habitat for salmonids, and permanent refugia for Giant Garter Snake and other amphibians.
Known Issues for Evaluation
- Managing channel habitat to accommodate all species of concern
- Retaining functionality of the canal for water supply and drainage on the Conaway Ranch, and for upstream and downstream users
- Channel maintenance necessary to preserve water supply and drainage functions while providing enhanced wetland habitat
- Managing invasive aquatic vegetation
- Preservation of farmland and compliance with Chapter 10, Yolo County Code of Ordinances, Habitat Mitigation Ordinance
