RECOVERY --- Fish Hatchery Coho Tanks Replacement, Warm Spring Dam/Lake Sonoma Project

 Work shall entail the replacement of ten 20-foot diameter by approximately 5-foot tall fiberglass tanks, which are currently being used to rear endangered (wild stock) Coho salmon. 

When originally constructed, the existing tanks were placed on a compacted foundation base consisting of a 6-inch sand layer and 12-inch minimum fill layer.  Since then, the sand layer on many of the tanks has been displaced enough to leave tank bottoms very poorly supported and prone to excessive leakage.  As a solution to the problem, the Government plans to replace the compacted sand layer base with a more permanent reinforced concrete slab.  Because this process will likely damage most of the existing tanks during their removal, the Government believes it is more practical to install new tanks.   

The Contractor shall remove and properly dispose of old tanks, purchase, assemble and install new tanks along with all associated attachments, such as piping and floats.  The Contactor shall remove the 6" compacted sand layer and prepare the subgrade for the concrete slab.  Disposal of the sand, or other excavated fill material can be done on-site, per the Contracting Officer Representative's (COR) direction. The Contractor shall provide the materials and labor in order to replace the 6" sand layer with reinforced concrete, construct a 3' reinforced concrete walkway around each Coho rearing tank.  The Contractor shall reinstall, or replace if necessary, all associated tank attachments back to design condition as well as test each tank to verify adequate operability.