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| German Gulch Fish Barrier |
Silver Bow County, Montana |
Primary Project Type: Fish Passage
Secondary Type: |
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A short reach in German Gulch was identified for the fish barrier due to the ver... |
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Primary Problem: Out-Competition of Native Fish
Secondary Problem: |
| Main Restoration Action(s): Construction of fish barrier |
| Native Fish Focus: Westslope cutthroat |
Is this project part of a watershed scale restoration? No
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| Project Dates: 2006 to 2007 |
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Initial Monitoring:
Restoration Implementation: The design phase of this project is complete. Project implementation is scheduled for 2006 or 2007.
Follow-up Monitoring: |
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Lead Agency:
Montana Fish, Wildlife and Parks
George Grant Chapter of Trout Unlimited
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| Project Partners: |
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| Project Location:
The proposed fish barrier is located in German Gulch approximately 2 miles upstream from the confluence with Silver Bow Creek, and immediately downstream of the confluence of Beefstraight, German and Norton Creeks. The project site is located within a reach of channel confined on both sides by generally vertical exposed bedrock. The elevation of the project is approximately 5480 feet MSL. The legal description is: NW1/4 of NE1/4 of Sec 26, T3N R10W.
For a map of the project area, click here.
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Project Description:
German Gulch is a third order tributary to Silver Bow Creek near Butte, MT. The stream has a drainage area of approximately 40 square miles and contains one of the most productive westslope cutthroat trout (WCT) fisheries in the Upper Clark Fork drainage. Brook trout are also present in German Gulch and associated tributaries, and one brown trout was observed near the mouth of German Gulch in 1984. Colonization of other invading species such as rainbow trout and brown trout from the Clark Fork River into German Gulch has been prevented by the toxicity of Silver Bow Creek.
Ongoing restoration of Silver Bow Creek will improve water quality in the future, and the possibility of fish migrating from the upper Clark Fork River into German Gulch may be possible within the next several years as water quality in Silver Bow Creek improves. The proposed barrier is intended to protect the native westslope cutthroat trout from hybridization with rainbow trout and additional competition from species like brown trout. The George Grant Chapter of Trout Unlimited plays an instrumental role in proposing, funding, and managing the restoration project in German Gulch.
Stream habitat improvement, acquisition of stream-side mining claims, water leasing, installation of a fish screen and several other projects are being developed for the German Gulch watershed. Several of these projects are being coordinated through the George Grant Chapter of Trout Unlimited, and it seems very likely that native cutthroat will benefit from this attention and effort. |
| Project Goals: The goals of the project are to create an in-stream fish passage barrier to maintain physical isolation for the Westslope cutthroat trout in German Gulch. The design phase of this project is complete and implementation is scheduled for 2006 or 2007. |
Project Methods:
In 1992, the conceptual design for a fish barrier was based on utilizing an irrigation diversion near the confluence with Silver bow Creek (Inter-Fluve 1992). Recent evaluations of German Gulch lead to the identification of an upstream reach of bedrock-confined channel that is more suitable for installation of a barrier. The general concept for the barrier is to use large rock from a nearby source placed between the bedrock walls to create a weir and a downstream apron. The basis for designing an appropriate configuration of the barrier is to limit upstream passage of fish based on fish swimming and leaping capabilities. Based on a review of available literature, a number of design criteria were identified that if satisfied should provide conditions that will inhibit upstream movement of fish in German Gulch. The design phase of this project is complete and implementation is scheduled for 2006 or 2007. The following are the design criteria identified, and a brief rationale based on the literature (2003 German Gulch Fish Barrier Design Report by Mainstream Restoration, Inc. and Allied Engineering Services, Inc.):
1. Provide a rock apron to prevent the formation of a plunge pool at the base of the barrier.
2. Disperse flow over the face of the barrier rather than allowing it to concentrate in one location.
3. Prevent flow between rocks comprising barrier. 4. Prevent flow velocities and depths over the barrier, which would allow fish to pass over the structure by swimming.
5. Provide smooth flow over the barrier, with as little variation as possible.
6. Provide a barrier with sufficient height to prevent fish from successfully leaping the obstruction.
For more details on the design of the German Gulch fish barrier, click here.
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| Monitoring Data and Collection
Methods: The existing population of westslope cutthroat trout in German Gulch and associated tributaries is relatively strong with numbers ranging from 24 to 69 WCT per 100 meters. Cutthroat trout outnumber brook trout in most areas in the drainage, but there is evidence that brook trout are beginning to outcompete cutthroat in one tributary (Norton Creek). Montana Fish, Wildlife and Parks and the U.S. Forest Service have removed brook trout in Norton Creek during 2003 and 2004 to attempt to reverse the trend of brook trout outcompeting cutthroat in this stream.
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| Was this project effective
and how was this determined? Effectiveness will be determined upon completion of the project.
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| Confounding Effects/Additional
Information: |
| Project
Specs (all specs are estimates): |
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Overall Estimated Cost:
Total cost estimate: $47,116
Site preparation: $11,100
Fish barrier construction: $6,600
Site Reclamation: $10,500
Additional costs: $18,916
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| For more information on this project
contact: |
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Dale Miller, Mainstream Restoration, Inc., Email: dmiller@mainstreamrestoration.com
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| This information
was collected by: Kristin Keith |
| Project last updated on: 12/22/2005 |
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