| Table M-1 | Proposed Modifications to Recreation Sites |
M.1 General
This study annex concerns the evaluation of the effects of reservoir drawdown on recreation areas and/or boat accesses along the Snake River from its mouth to the Idaho border, approximately 230 river kilometers (140 river miles). Affected reservoirs include Lake Sacajawea (Ice Harbor Reservoir), Lake West (Lower Monumental Reservoir), Lake Bryan (Little Goose Reservoir), and Lower Granite Lake (Lower Granite Reservoir).
M.2 Methods
Each of the 33 recreation areas were evaluated and assigned a ranking of low, medium, or high regarding the potential impact of the drawdown. Table M1 represents modifications to recreation sites. This annex does not attempt to evaluate post drawdown recreation usage at each of the affected recreation areas. That topic is addressed in other sections of this study.
| Table M1 Proposed Modifications to Recreation Sites | |||||||
|---|---|---|---|---|---|---|---|
| Location | Launch Ramp |
Parking | Other | Access Road |
Parking | Launch Ramp |
Other |
| Lake Sacajawea (Ice Harbor Reservoir) | |||||||
| North Shore Ramp | 2 | 2,800 | Toilet, shelter | ||||
| Charbonneau | 2 | 5,000 | Toilet, shelter, swim beach, marine dump station | 1,710 | 5,600 | 2 lane | Toilet |
| Levy | 2 | 5,500 | Swim beach, handling docks | 735 | 5,600 | 2-lane ramp | Toilet |
| Fishhook | 2 | Boat moorage, swim beach, and fixtures | 2,200 | 2-lane | |||
| Windust | 1 | Swim beach | 2,200 | 2 | |||
| Matthews | 1 | Handling docks | 2 | ||||
| Lake West (Lower Monumental Reservoir) | |||||||
| Devils Bench | 2 | 25-car | 2 vault toilets | ||||
| Ayers Boat Basin | 2 | 4 handling docks, 2 picnic shelters, vault toilet |
|||||
| Lyons Ferry State Park | 44-car-trailer | Flush toilet facility, swim beach and
fixtures, 4 picnic shelters |
8,000 | 2 | Vault toilet | ||
| Lyons Ferry Marina | 2 | 44-car-trailer, 22-car |
Flush toilet facility, handling docks, swim beach and fixtures, restaurant, and maintenance building | ||||
| Texas Rapids | 2 | 2,100 | 2 | ||||
| Riparia | |||||||
| Lake Bryan (Little Goose Reservoir) | |||||||
| Little Goose Landing | 2 | Handling docks | |||||
| Central Ferry State Park | 4 | 73 car-trailer | Handling docks, marine dump station | 2,500 | 6,700 | 2 | Vault toilet |
| Garfield County Ramp | 2 | Gravel | Vault toilet | ||||
| Willow Landing | 2 | Handling docks, vault toilet | |||||
| Illia Landing | 2 | 11-car trailer | Vault toilet, picnic tables, mooring docks | ||||
| Illia Dunes | |||||||
| Boyer Park and Marina | 3 | Flush toilet, gas dock facility, marine dump station, hotel, restaurant, handling docks, swim beach | 740 | 6,700 | 2 | Vault toilet | |
| Lower Granite Lake(Lower Granite Reservoir) | |||||||
| Offield Landing | 1 | 15-car trailer, 10 car |
Handling dock, sun shelter, vault toilet | ||||
| Wawawai County Park | |||||||
| Wawawai Landing | 1 | 27 car-trailer | Swim beach and fixtures, picnic facilities, chemical toilet | 3,911 | 5,000 | 2 | Vault toilet |
| Blyton Landing | 1 | 17 car-trailer, 19 car |
|||||
| Nisqually John Landing | Picnic facilities, vault toilet | ||||||
| Chief Timothy State Park | 4 | Car-trailer | Handling docks, marine dump station | 1,470 | 6,667 | 2 | Vault toilet |
| Hells Canyon Resort (Redwolf Marina) | 2 | Marina, gas dock facility, marine dump station, log breakwater, handling docks | 611 | 5,000 | Vault toilet | ||
| Greenbelt Ramp and Boat Basin | 2 | 34 car-trailer, 34 car |
Floating boathouse, marine fueling station, handling docks | 660 | 5,000 | 2 | Vault toilet |
| Southway Ramp | 2 | Chemical toilets, handling docks | 1,470 | 5,000 | 2 | Vault toilet | |
| Swallows Park | Swim beach facilities, handling docks | 1,223 | 5,000 | 2 | Vault toilet | ||
| Hells Gate State Park | 6 | X | Handling docks, marina, commercial moorage, marine fueling station, marine dump station, swim beach facilities | 1,223 | 6,667 | 2 | Vault toilet |
| Chief Looking Glass Park and Marina | 2 | marina | |||||
| Clearwater Park | X | ||||||
| Clearwater Ramp | 2 | ||||||
Considering existing site facilities, features, usage, access, and topography, the study team determined the general impacts of drawdown and mitigative actions required to maintain water access to the post drawdown water levels. The team determined that it would be best to close some sites because of the post drawdown water level and/or the site’s proximity to dams and other areas that would remain operational. Estimated post drawdown water elevations were derived from 1957 topographic surveys.
M.3 Assumptions
The study team assumed that the Corps would continue to manage and maintain currently owned lands within the study area. It was assumed that lessees would not be responsible for removal of facilities such as marina moorage, restaurants, hotels, or facilities left in-the-dry as a result of drawdown. This annex does not address mitigation to landowners or lessees for direct effects on current businesses and/or personal liabilities.
M.4 Site Modifications
Site modifications include actions such as abandoning part or all of the facility, demolition of part or all of a facility, and relocation boat ramps, parking lots, and visitor facilities. Table M1 summarizes the modifications at each site.
Demolition of facilities is the removal of all buildings, roads, parking lots, utilities, guardrails, light poles and restoring the site to a relatively undeveloped condition. It does not include removal of vegetation. For some recreation areas the entire area is to be demolished. For others, only marinas and boat ramps are to be demolished. Functions such as day use and camping may continue.
For those recreation areas where boat access to the river is necessary, the existing ramp and associated features will be demolished and a new ramp, parking, and facilities constructed as appropriate for the new river conditions.
M.5 Conclusions
Two of the 33 recreation areas evaluated for this study would not be affected by the drawdown; two would be closed to river access and 11 would close entirely. The remaining 18 areas would require modifications for river access. Nine marinas or boat moorage facilities would no longer exist. All swimming beaches, as they currently exist, would be impacted due to severe changes in the water elevations. For sites with irrigated lawns, wells or extended river intakes would be required to ensure continued vegetation. Table M1 provides a detailed listing of all the recreation areas evaluated, with the associated site modifications resulting from drawdown.
List of Appendixes
Annex A Turbine Passage Modification Plan
Annex B Dam Embankment Excavation Plan
Annex C Temporary Fish Passage Plan
Annex D River Channelization Plan
Annex E Bridge Pier Protection Plan
Annex F Railroad and Highway Embankment Protection Plan
Annex G Drainage Structures Protection Plan
Annex H Railroad and Roadway Damage Repair Plan
Annex I Lyons Ferry Hatchery Modification Plan
Annex J Habitat Management Units Modification Plan
Annex K Reservoir Revegetation Plan
Annex L Cattle Watering Facilities Management Plan
Annex N Cultural Resources Protection Plan
Annex O Irrigation Systems Modification Plan
Annex P Water Well Modification Plan
Annex Q Potlatch Corporation Water Intake Modification Plan
Annex R Other River Structures Modification Plan
Annex S Potlatch Corporation Effluent Diffuser Modification Plan
Annex T PG&E Gas Transmission Main Crossings Modification Plan
Annex U Hydropower Facilities Decommissioning Plan
Annex V Concrete Structures Removal Plan
Annex W Implementation Schedule
Annex X Comprehensive Baseline Cost Estimate
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