The lower Weber River has been extensively modified and channelized in the last 50 years or so, with the biggest impacts occurring in conjunction with the construction of the I-84 freeway around 1970. These impacts have had a negative effect on the aquatic and riparian habitats of the river, reducing the diversity of water depth and flow rates that the river once provided. In particular, it has been found that juveniles of the native Bluehead Sucker lack much of the habitat that they need to grow to maturity, resulting in a lack of recruitment and a declining population. In addition, the river has been cut off from much of its former floodplain, causing a reduction in the health and quantity of riparian vegetation.

The objective of this project is to reconnect a system of overflow channels that used to flow during the spring runoff but have been dry since 2011, due to excessive downcutting in the main channel. Water will flow back into the main stem of the river at the downstream end of the channels and may also fill the old borrow pit on UDWR land, creating a seasonal wetland.

The Weber River is home to several imperiled native fish species, including the bluehead sucker and Bonneville cutthroat trout. Restoration of this stretch of the river will provide a unique opportunity to create and enhance the habitat for these aquatic species, as well as establish riparian flora and fauna on a site that is now mostly barren. The bluehead sucker populations in the Weber River basin have been shown to be genetically distinct from the populations in the Colorado River basin. If the Weber River population is declared to be a separate species, it will increase the urgency of measures to slow and reverse the current population decline. The bluehead sucker here is suffering from a juvenile rearing bottleneck, and the creation of improved habitat may significantly increase the survival of juvenile fish. This project adds to other efforts to create habitat for the bluehead sucker along the lower Weber River, including the new channel constructed in 2020 on this same property. Thus it has the potential to help keep the bluehead sucker from being listed as an Endangered Species.

This project is part of a large-scale restoration plan along the reach of the Lower Weber River. It occurs within the Ogden River--Cottonwood Creek reach of the Weber River, which has been highly degraded and modified, negatively affecting macroinvertebrates. This is a core area of bluehead sucker and Bonneville cutthroat trout habitat, two species that have been identified as indicators of success in the 2014 Weber River Restoration Plan. That plan identified past and current habitat loss due to channelization and flood control actions as a high threat within the Lower Weber River. The Lower Weber River Watershed Plan, commissioned by Ogden City, describes the river between the mouth of Weber Canyon and the confluence with the Ogden River as "a significant stronghold for bluehead sucker." The report goes on to state that historic flood overflow channels have been filled in or disconnected from the river, resulting in an unstable river channel that no longer functions naturally. "Water quality degradations and habitat alterations have likely diminished the health of the fishery," and stream restoration projects could improve bluehead sucker rearing habitat and benefit macroinvertebrates. The report recommends "improvement of the natural characteristics of the channel by removing levees, digging side channels, and improving riparian conditions." A new side channel was dug here in 2020, and this project will reconnect existing natural side channels. The 2017 Western Weber County Resource Management Plan recommends the protection of "the Weber River floodplain, wetland areas associated with the meander corridor, and streamside vegetation." It also recommends providing "habitat for plant communities, wildlife, and fisheries," including "unique ecological communities for rare, threatened or endangered species." This project accomplishes all of these objectives, setting aside a mile of the river that will be protected from development as well as improving the habitat for imperiled species such as the bluehead sucker and Bonneville cutthroat trout. The Utah Division of Water Quality has identified hydromodification as a key feature of the degradation of Weber River habitat. This project will take steps to reverse this hydromodification, and a similar project was identified in 2004 under a proposal to the Army Corps of Engineers Section 206 ecosystem restoration program. The entire program was never funded, but that proposal has been maintained with the Corps. The Utah State Resource Management Plan has identified the preservation and enhancement of rivers and floodplains as important objectives to consider when planning projects. Additionally, wetlands and riparian areas have been identified as key resources to provide both environmental and economic benefits to Utah communities. Recreation has also been called out as essential to Utah's ecological and economic vitality into the future. This project addresses these RMP objectives and also will help to bring the community together around this rare resource, the River.

This project will have little impact on fire and fuels. However, the re-establishment of the overflow channels will contribute to healthier vegetation along their banks that will better resist wildfire.

This project ties in with other projects on the Lower Weber River to create and protect habitat for the bluehead sucker. An Endangered Species listing for this fish could create restrictions on the timing and quantity of diversions from the river, and the Weber Basin Water Conservancy has stated that it is a priority to avoid such a listing. Thus this project has the potential to help protect vested water rights and water supplies. By creating a more natural floodplain and streambank profile, the project will also increase the river's ability to accommodate and absorb floodwaters, reducing the flooding risk to neighboring properties, and the establishment of riparian vegetation will reduce the amount of sediment currently eroded from raw banks during high water events.

A stream alteration permit has been obtained, and a floodplain certification is pending. A cultural resource assessment has determined that there are no resources in the affected area. Due to the location of this project, we will also work with Davis and Weber Counties FEMA coordinators to ensure that any proposed actions do not negatively affect flood levels.

Construction will be done during the next available period of low water. Grade control structures consisting of natural boulders and native rock material will be used to divert water into the channels when the flow of the river exceeds approximately 1,000 cfs. A grade control structure will also be built at the downstream end of the overflow channel, where it returns to the main stem of the river. Disturbed areas will be reseeded with native plants, and dormant willow cuttings will be planted where possible.

Weber Pathways, dba Trails Foundation of Northern Utah (TFNU) currently monitors parts of the Weber River Parkway on a regular basis, to identify hazards and eliminate noxious weeds. These efforts by TFNU personnel will continue after completion of construction. UDWR has been conducting fish population surveys along the lower Weber River and is planning follow-up surveys along this stretch.

Trout Unlimited has worked extensively along this reach to evaluate and improve aquatic habitats in coordination with the Utah Division of Wildlife Resources. Utah Water Watch and local volunteers have helped to monitor the project success. TFNU works with local volunteers and interns to provide stewardship for the project and adjacent areas.

Over the long term, the project should require very little maintenance, but the site will be monitored for unexpected erosion, flood damage, and noxious weeds, and the appropriate corrections will be undertaken. Disturbed areas will be reclaimed with native and firewise species of grasses and forbs. As the land owner, TFNU will continue to provide a stewardship presence on the site.

The reconnection of the overflow channels will not only take flooding pressure off the Weber River during high runoff years, it will also provide an opportunity for groundwater recharge when the old borrow pit is filled with water, creating a seasonal pond. In this way the project could lead to the sustainable storage of water supplies as well as the creation of three acres of wetland habitat. Blackner's Bend also provides access to the river for angling and wildlife watching opportunities. The project site is currently accessed from South Weber's Fisherman's Point Trailhead by a primitive single-track trail used by anglers. This project will enhance opportunities for angling by improving fish habitat. Future phases are envisioned to include a 10-foot wide non-motorized public pathway and a bridge to the Uintah Springs Business Park on the north bank. This pathway and bridge will be a vital link in the connection of the Bonneville Shoreline Trail, Weber River parkway, and Centennial Trail loop, enhancing the community's opportunities for transportation and recreation by foot, bicycle, and horse, as well as providing a place for wildlife viewing.

07/18/2022

10/22/2022

2023

Heavy equipment was used to bring large boulders onto the site and place them in the river according to the designs specified for the grade control structures and to shape the entrances to the historic overflow channels to the dimensions specified in the plans.

The installation of the grade control structures was very successful, and to the casual observer it is not apparent that the river was modified in any way. At low water, these structures allow all of the water in the river to pass through the main channel, but at flows of more than approximately 1,000 cfs, they will divert some of the flow into the historic overflow channels. This diversion will reduce flood risk in the main channel as well as re-engage the historic floodplain, providing increased habitat for aquatic, avian, and terrestrial species.

The project has not yet experienced the high flows that will be necessary to engage the overflow channels, but we expect that the grade control structures and channels will function as designed. No future management should be needed, but the site will be monitored annually during both high water and low water to make sure that it is functioning correctly, and appropriate modifications will be designed if necessary. This report was submitted by Geoff in December 2022.