Alternatives for Middle Fork Access Above Interbay Powerhouse


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Background. In the Foothills Angler Coalition statement of interests, under the recreation subtitle, a specific item was included regarding public access to the Middle Fork above the Interbay powerhouse, through the PCWA fenced yard. During the negotiations PCWA took the position that access through the fenced yard would cause security problems. An alternative was explored whereby a walkway would be constructed on the face of the powerhouse outlet; this alternative was determined to be infeasible due to issues raised by USFS regarding ADA requirements. In the subsequent discussions, a new public access trail below the Interbay dam was considered as a tradeoff for access above the powerhouse. The subsequent collaborative agreement included construction of this trail as a public amenity to be provided at PCWA’s cost. This item was also included in the FLA, and was discussed in the FERC EIS. Since then, PCWA commissioned a technical study to determine whether trail construction was feasible and practical from a public safety standpoint. The engineering firm concluded that due to the combined steep nature of the terrain and the apparent instability of the soils on which the trail would be constructed, the trail construction costs would be prohibitive, thus rendering the project infeasible. PCWA furnished the engineering report to the interested parties, and a meeting is scheduled on this subject for November 13, 2012. Foothills Angler Coalition wishes to explore further the original request for access above the Interbay powerhouse, and has investigated a number of access alternatives that appear to be feasible. These are set forth below.

Alternatives for Middle Fork access above the powerhouse. The three alternatives that FAC has investigated are set forth below, and are depicted on the two Google Earth images (numbered 1 and 2) that are attached.

1. Improve the existing trail (faint and obscure as it is) that begins just west of the gate to the powerhouse yard on the south side of the powerhouse access road. This informal trail begins on the south side of Interbay Road just before it ends at the fenced powerhouse yard. From the road it climbs straight up the steep cliff; after about 100 feet, it curves in an easterly direction, passing just above the fence that is upslope from the yard, and leads to the penstock feeding the powerhouse. At that point it is necessary to crawl under the penstock and continue on the trail downward to the that leads to the upstream MF area and PCWA’s gaging station. This access method would require construction of a trail (presumably with switchbacks) up the southerly slope and eastward to the penstock. At that point, a method of safely crossing over the penstock would have to be constructed. From there, the trail would need to be improved down to the river near the gaging station.

2. Add interior fencing within the powerhouse yard along its southerly edge to form a narrow corridor against the south bedrock cliff that forms a wall within the existing fenced area. This alternative would entail creating an opening near the entrance gate to the yard; adding interior fencing adjacent to the bedrock cliff that exists on the yard’s southerly edge; and creating a second opening at the rear of the yard. The fencing would create a narrow interior corridor wide enough for pedestrian passage–about 18″. This would allow access for anglers and hikers, while preserving essential security for the powerhouse facilities. If there is a concern about needing that room in case of emergency, or when large scale repairs or maintenance are required, the interior fencing could be designed to be temporarily removable.

3. Improve the existing dirt road that parallels (roughly) the penstock up to the top of the ridge. There is an unpaved but serviceable road that takes off from USFS Road 23 (the Blacksmith Flat Road) and leads to a gate near the top of the penstock, where PCWA has penstock- related facilities. The gate is locked, and ownership of the gate is unknown to FAC. Beginning at the gate, there is a steep dirt road that roughly parallels the penstock, heading downward and ending near the river above the powerhouse, with a number of spurs leading to the penstock; it appears that this road is used by PCWA to service the penstock when needed. Under this alternative, anglers and others who desire access to the area above the powerhouse would be allowed to use the road leading down from the gate to the river. FAC member Bill Carnazzo and others hiked up this road from the river to near the gate, a distance of approximately 1.5 or 2 miles because of the numerous switchbacks. The road is, except in one small area, quite usable by 4WD vehicles. Minor repairs and clearing are necessary on the one small portion of the road. This alternative would require clear delineation of ownership of the road and the surrounding land, but it appears from Assessor’s maps that it is owned by the USFS or BLM. There may well be other alternatives, possibly including resurrection of the concept of a walkway along the front of the powerhouse; aside from that these are the only possibilities that we have been able to think of.