MEMO

To: NCRA Board of Directors From: Executive Director Mitch Stogner Date: April 9, 2014 Item: Item H.1 - Report on Status of Rocky Gulch Crossing Conditions __________________________________________________________________________________________ The NCRA was contacted by the California Department of Fish and Wildlife regarding additional deterioration of the 60” diameter corrugated metal culverts at Rocky Gulch at Bayside south of Arcata. Numerous photos of current and previous conditions were provided by various individuals that are catalogued in NCRA files. A site visit on 3/24/14 was made with parties noted below. A temporary resolution was addressed that should be completed by summer of 2014 or earlier subject to any requirements that may be imposed by other agencies that must be notified of any proposed temporary and permanent restoration activities. The following agencies are involved:

1. Calif. Coastal Commission 2. Humboldt Bay Harbor District 3. Army Corps of Engineering/National Marine Fisheries 4. North Coast Regional Water Quality Control Board 5. US Fish and Wildlife Service (Tidewater Goby) 6. Caltrans

In addition, a form LSA: Notification of Lake or Streambed Alteration, will be completed by the NCRA for review by the California Department of Fish and Wildlife in connection with the temporary restoration. A permanent restoration will be subject to further review based on engineering designs. The NCRA project engineer estimates that the cost is $150,000 without benefit of design drawings and not including the temporary construction of a fish by-pass facility around the construction site. All agencies noted above will also be involved in permitting this restoration. The permanent crossing must be constructed during periods of minimum fish passage through Rocky Gulch. The permanent restoration may not occur until 2015. Funding must be provided through a grant. The CDFW has indicated an interest in assisting with the search for grant funding. Cal Trout has previously used grant funding for fish passage improvements to Rocky Gulch and Rocky Creek. Restoration of the culverts would be consistent with their restoration goals.

Figures 1 and 2 below indicate current deteriorated conditions based on photos taken on 3/24/14. Figure 3 is an example of a potential restoration solution (culvert under US 101 at Rocky Gulch). Extract of CDFW comments from site visit:

Rocky Gulch Culverts Field Site Visit, March 24, 2014/low tide from CDFW

Problem: Failing and badly rusted with holes twin corrugated metal culverts approx. 5-feet in diameter (installed ~1970s). Southern culvert with collapsed outlet, stream flow and some capacity left. Northern culvert with collapsed sidewalls and inlet and with restricted stream flow and very little capacity left. Gravel fill/railroad prism above culvert with perched rails, hanging/disconnected rail ties, and large unstable void/hole that appears to feed material down into northern culvert. The void/hole appears to be inundated during extreme high tides, up and over (racked debris indicates), as well as, possible upwelling up through the void. Fish passage and entrapment concerns, and eminent total failure of the culverts and further deposition of railroad prism material into stream. Temporary Fix / Until Permanent Fix can be Implemented ASAP: Stay out of the wetted channel, cut/remove collapsed portion southern culvert outlet, cut/remove collapsed portion northern culvert inlet, buildup railroad prism over outlet to prevent overtopping/fish stranding in void/hole and reduce railroad prism over inlet to facilitate a low point exit should fish get stranded in hole. Need to submit Lake and Streambed Alteration Agreement Notification (substantial); Also discussed with NCRA need to engage other jurisdictional agencies on proposed temporary fix such as Calif. Coastal Commission, Humboldt Bay Harbor District, Army Corps of Engineers/National Marine Fisheries Service, North Coast Regional Water Quality Control Board, US Fish and Wildlife Service (Tidewater Goby). In attendance:

Doug McCorkle - NRCA Darren Mierau – CalTrout Jeff Anderson – Northern Hydrology and Engineering Pete Oringer -Timber Heritage Association Michelle Gilroy – CDFW Fisheries David Manthorne – CDFW LSAA Clare Golec – CDFW LSAA

Figure 1: Railroad Prism Collapse and Culvert Inlets at Rocky Gulch Stream Crossing Looking West.

Temporary Restoration

Undermined track by tidal action. Restoration with rock dam on far side of tracks and open near side to drain to pool below. Remove debris from top of culverts. Failed, water saturated and undermined roadbed soils causing riprap to collapse on culvert bending culvert metal causing partial blockage of fish passage at both ends. Remove bent portions of culvert metal partially blocking fish passage on both sides of roadbed

Figure 2: West Culvert Outlets at Rocky Gulch Stream Crossing. (Worst case)

Figure 3: Alternative Permanent Resolution. (Similar to existing Highway 101 concrete box culvert at Rocky Gulch)