| Condition or Opportunity | Price-Stubb Dam Removal (restore natural channel) | Price-Stubb Ladder |
|---|---|---|
| Hydropower The Federal Entergy Regulatory Commission has issued a license to a private citizen to construct a hydroelectric power plant at the dam. |
Without the dam, hydroelectric development would not be possible. | Conceptual drawings for the hydropower plant indicate it would be possible to design and construct both facilities. The license includes a commitment to allow for a fish ladder. |
| Railroad and Landslide Stability A landslide exists on the steep cliff above the dam on river right. Railroad tracks are between the river and the toe of the slide. |
Geologists and engineers are investigating concerns that removal of the dam may affect stability of the landslide. If so, cost-effective mitigation measures would need to be determined. | No impact is anticipated. |
| Downstream Municipal Water Treatment Plant Clifton Water Company diverts and treats Colorado River water approximately 6 miles downstream from the dam. |
It is necessary to determine the chemical, bacterial and particle size composition of the sediment that would be released if the dam is removed. The sediment is being tested and the information will be made available to Clifton Water to determine if additional treatment processes would be necessary. | Temporary increases from the construction impacts are expected |
| Ute Water Conservancy District (Ute) Pumping Plant
Intake Ute pumps water from the river to their treatment plant. Ute's intake is at the upstream end of the pool behind the dam. |
At times of the year when streamflows are low, there is concern that removal of the dam may cause the water levels of the river to fall below the pumping plant water intakes. | The pool of water behind the dam would not change so effects to Ute Water's ability to pump from the river would not change. |
| Spring Flodding of Ute Water Pumping Plant During sping runoff, Ute's pumping plant floods |
Removal may have the beneficial effect of decreasing the occurrence and magnitude of flooding since river water levels would be reduced if the dam is removed. | No change from existing conditions |
| Interstate 70 (I-70) The 4-lane highway is next to the river in the narrow canyon. |
The Colorado Department of Transportation is concerned about the longevity of the riprap which protects the foundation of I-70 (similar to concerns of the railroad). | There would be no effect on the I-70 foundation. |
| Reclamation's Colorado River Pipeline Reclamation has a pipline (the Colorado River siphon) in the river bed about one-half mile upstream of the Price-Stubb Diversion Dam. It carries water from the Government Highline Canal to the Orchard Mesa Power Canal. |
If the dam is removed, the velocity of the water in the river will increase. As the velocity increases, the amount of scour increases. Reclamation is concerned that the scour could extend upstream and to expose/damage the pipline. | There would be no change in the threat to the Reclamation's pipeline. |
| Boating on the river The diversion dams currently preclude boating on the river in the miles from the 12-foot-high Grand Valley Project Diversion Dam to the 8-foot-high Price-Stubb Diversion Dam. |
Removal of the dam may make the Colorado River boatable by rafters and kayakers. Based upon interest that has already been generated in this possibility, boating use would likely significantly increase. The probable put-in site would be a couple of miles upstream of the dam at Island Acres State Park, from which boaters could float down the river to a variety of take-out points. This might increase the liability exposure to GVIC, and may disturb passage by endangered fish. | Potential for boating on this stretch of the river would remain unchanged. The existing structure is a barrier to all boating activity. Increased recreation on the river might marginally increase in this stretch of the river. Increased liability exposure to GVIC would be limited. |
| Cost Goal is to minimize cost while providing effective fish passage. Costs include all construction costs, slide monitoring (if necessary) and operation and maintenance costs. |
Removal appears to be the least costly option. Costs would include measures to increase to stabilize and monitor the landslide, protect the railroad and I-70 foundations, and protect the UWCD pumping plant intake. | Based on costs for constructing and operating the Redlands Fish Ladder, it is anticipated that a ladder would cost more than the removal option. |
| Dam Ownership, Safety and Liability Mesa County and Palisade Irrigation Districts (MCID & PID) own the Price-Stubb Diversion Dam. People have drown in the turbulent water below the dam. |
MCID & PID would have to approve removal of their structure. Removal may alleviate public safety/liability concerns at this dam site. | MCID & PID would need to approve modification of their diversion dam. Public safety and liability cncerns would need to be addressed, for both the diversion dam and the ladder. |
| Ease of Fish Movement It is challenging to design a passageway or ladder that endangered fish species can find and use successfully. |
Removing a man-made barrier and letting the river channel return to natural conditions would be the least stressful passage option for the endangered fish species. | Successful use of the Redlands fish ladder by 28 Colorado pikeminnow and innumerable native fish has occurred in the last two migration seasons. |
| Historic Resource Protection The Price-Stubb Diversion Dam is eligible for listing on the National Register of Historic Places. |
Removal would adversely affect the historic dam. Reclamation will consult with the Colorado State Historic Preservation Office to determine effects of removing the abandoned and historic dam, and consider measures that could be taken to offset adverse effects. | A fish passage structure would require modification to the dam. Consultation with the Colorado State Historic Preservation Officer would determine measures needed to avoid adverse effects. |
| Fish and Wildlife The existing dam has served as a barrier to the upstream movement of nonnative fish thus reducing competition and predation to favor the native fish. |
Non-native fish would be able to move upstream of this historic barrier, and would compete with native fish. | A fish ladder could be installed with a fish trap so nonnative fish could be selectively prevented from populating the habitat above this historic barrier. |