Pine Lake is a very popular destination for fishing, camping and other outdoor recreation activities. The Dixie National Forest (DNF) operates a developed campground, restrooms and ATV facilities at the lake. The UDWR owns the dam and water stored in the lake. The lake is stocked annually with rainbow and cutthroat trout. The DWR also owns the Water Rights to Clay Creek, which is diverted via a buried pipeline into Pine Lake. Clay Creek keeps the lake full and helps to mitigate low oxygen levels during winter, which helps to reduce winter fish kills. The diversion grate on Clay Creek often clogs with gravel, sand and debris, preventing water from flowing into Pine Lake. The water pipeline runs adjacent to Clay Creek and then over to the lake. The stream bank has eroded and exposed about 20 feet of the pipeline, which could be easily damaged in a flood event. The diversion structure needs some modifications and improvements made to prevent clogging of the grate and rock needs to be installed along the stream bank to protect the pipeline and prevent damage to it. 800 feet downstream from the diversion structure old rock grade control structures have washed out and the stream is down-cutting. Future flood events could cause continued down-cutting of 6 feet or more and threaten the footings on the foot bridge across the stream and cause problems at the diversion structure and pipeline. Rock grade control structures need to be rebuilt to maintain stream bed elevation and prevent future problems to infrastructure.

1. Make modifications to diversion structure to prevent grate from continuing to plug. 2. Install rock along stream bank to protect water pipeline. 3. Install rock grade control structures to prevent stream down cutting.

If the diversion structure is not improved it will continue to plug and water will not flow into Pine Lake. If the water pipeline is not protected and it gets broken, water will not flow into Pine Lake. If the stream continues to down-cut the footings for the footbridge could be undercut and collapse and eventually the diversion structure may be above the stream elevation and water would not flow into Pine Lake.

Project meets the following DWR goals: Resources goal: Increase fish and game populations to meet management plan objectives and expand quality fishing and hunting opportunities. Constituency goal: Achieve broad-based support for Division programs and budgets by demonstrating the value of wildlife to all citizens of Utah. Improve communications with wildlife organizations, public officials, private landowners and government agencies to obtain support for division programs. Expand programs to recruit and retain young hunters, anglers and wildlife watchers. Project meets goals of Dixie National Forest to provide quality recreation opportunities.

Not applicable

Improves water quality by increasing oxygen levels in Pine Lake. The lake has heavy aquatic vegetation and when it dies and decays oxygen in the water is used up. Project provides water inflow to Pine Lake to keep the lake full.

Dixie National Forest will complete NEPA under a CX: maintenance of existing structures.

A private contractor will be hired to haul large rock to the site and use a small excavator to place it along the stream bank to protect the water pipeline and rebuild rock grade control structures. A front-end loader will be needed to move rock from the dump site location to where it is needed along the stream. Rock will be hauled 30 miles from the BLM Casto Canyon rock pit. A Dedicated Hunter will construct a new steel grate for the diversion structure. DWR personnel will modify concrete box structure housing the headgates and install the new steel grate.

Fish population gill netting is conducted every three years at Pine Lake. Annual visual inspection of the diversion and pipeline route occurs every year.

Dixie National Forest -further discussions are occurring with the DNF concerning plans, timing and funding options.

Project will maintain fishing and recreation values at the lake. The lake will continue to be managed for public angling and recreation benefits.

Not applicable

10/04/2016

10/11/2016

2017

The DWR heavy Equipment crew hauled large rock to Pine lake for the project. A front-end loader was used to move rock from the dump site location to where it is needed along the stream.The crew used an excavator to place the rock along Clay Creek stream bank to protect the exposed water pipeline and rock was placed around the foot bridge footings to prevent them from being undercut by stream erosion and downcutting. The crew also built rock 6 grade control structures below the foot bridge where old riprap material had wash away and stream was downcutting. Rock was also placed around the diversion structure and as bank protection above and below diversion structure. A Dedicated Hunter constructed a new steel grate that is 18" tall for the diversion structure. DWR personnel added concrete to the existing concrete box structure housing the headgates to raise its height and installed the new steel grate on top of the collection box. Area was cleaned up and reseeded.

Since the project was completed heavy summer thunderstorm runoff has come down Clay Creek and the grade control structures have worked excellent in preventing the stream from downcutting and maintaining upstream infrastructure of the foot brodge, water pipeline and diversion structure. The diversion structure did not clog up. Sediment agraded above the structure to the height of the new steel grate. Sediment was moved on downstream below the grate and did not deposit and cover the grate as in the past. The diversion structure functioned great all summer. In September 2017 a runoff event flushed a ton of small sediment down the stream into the diversion structure. This smaller sediment (pea sized gravel) fell through the grate and completly filled the collection box and entrance into the water pipeline. This was unusal. In my 20 years of working with this diversion there has never been an event that deposited so much small pea sized sediment to fill the structure and block the pipeline.

In fall 2017 the diversion box will be dug out, the steel grate removed and the collection box cleaned out to open up the pipeline again. If this happens in the future a new plan may need to be designed. Fish monitoring will continue at Pine Lake. Rainbow trout winter carry-over from 2016 to 2017 was improved.