PROJECT: Fish Hatchery Raceways
LOCATION: Juneau & Snettisham, AK
OWNER: Douglas Island Pink and Chum Hatcheries
APPLICATOR: HPC Urethane
COATING SYSTEM: Polyshield HT™ with AE-4 (adhesion enhancer)
TOTAL AREA: 3,870 m2
COMPLETION DATE: 1999
Every year, more than 126 million salmon leave Alaska’s Douglas Island hatchery, bound for the Pacific Ocean. The hatchery is an important local industry, but the entire crop was put at risk in 1999 following an outbreak of whirling disease. The illness impairs the ability of fish to swim, and is spread by a worm so small it can travel through tiny cracks in the concrete chutes. The hatchery needed a protective lining that would allow them to immediately quarantine infected fish. SPI’s polyurea coating was chosen as it could be applied directly to the hatchery walls, rather than resorting to a costly replacement of the entire chute.
The concrete was prepped with a high-pressure wash using a biodegradable soap, then dried and vacuumed. The hatchery sprayed the walls with a Polyshield HT™ polyurea coating, combined with AE-4 (adhesion enhancer) to avoid the need for an expensive primer. This performance coating was applied directly to the concrete at a depth of 2.5- 12.5mm. The rapid curing properties of the protective lining allowed the hatchery to quickly resume business.
The owner was extremely pleased with the fast cure time of the polyurea coating, which allowed them to put the raceways back into service immediately. The original contract was awarded for 8 raceways. Due to the excellent performance of the protective coating, the remaining 27 raceways were awarded to the contractor the following year. Today, 18 years after the initial project, the high performance coatings remain as effective as ever, and the hatchery has stayed in operation and disease-free.