Methow Fish Hatchery BGM Install

LOCATION:  Winthrop, Washington

TIMEFRAME: 2017

SCOPE OF WORK: 

Furnish and install Bituminous Geomembrane as specified for project over area approximately 65’ x 115’.  On subgrade prepared by others Layfield laid out and seamed liner panels, sealed liner to; 3 each concrete openings in the floor, approximately 3’ x 9’ each and 8 each pipe penetrations for pressure relief valves. In addition, Layfield crew sealed liner to concrete on two ends of pond concrete wall and floor using approximately 145’ LF total of batten bar.  Layfield provided QA/QC for work performed. 

PROJECT PARTNERS: Owner: Washington State Fisheries Engineer: HDR Engineering Installation: Layfield USA Corporation Supplier: Axter Coletanche

Background Information and Challenge

Department of Fisheries felt the liner system they had previously was inadequate.   The location of the project is remote and it was always difficult to get qualified repair technicians to site for repairs to their 45 Mil RPE liner.  Bank on pond was frequently walked on and it was a safety issue the liner would be slick.  While the pond was fenced in deer were known to get over the fence. 

The install window for the project required the work to be done over a two week time period at the 1.pngbeginning of November when the weather is expected to become extremely inhospitable with cold temperatures, snow and ice.

Solution

The owner was recommended by the engineer to use Bituminous Geomembrane manufactured by Coletanche.  This geomembrane is extremely durable and resistant to puncture having polyester scrim reinforcement and can be repaired using propane torch.  After recent project success on the Roza Irrigation Pond, 1.8 Million Square feet of ES-2 Bituminous Geomembrane installation, the engineer was confident they had a  liner that would give Department of Fisheries everything they were looking for in a liner installation. 

Results

Layfield crew did an amazing job at picking up on new installation techniques and working in extremely challenging weather conditions. The liner was able to be installed with snow and water still on the panels. The attention to detail by the Layfield crew ensured we would have many more opportunities to perform installations for Axter Coletanche Bituminous Geomembranes and demonstrated why a quality oriented installation team with expertise in laying Geomembranes was essential to project success. 

There is significantly more labor for installing a BGM type liner which needs to be accounted for in the budget. This includes significant time for troweling the molten bitumen and primer coating surfaces for attachment of batten bar.