Batavia Kill Watershed District Dams: Emergency Action Plans & Post-Irene Engineering Services

Batavia Kill Watershed District Dams: Emergency Action Plans & Post-Irene Engineering Services
Batavia Kill Watershed District Dams: Emergency Action Plans & Post-Irene Engineering Services
Batavia Kill Watershed District Dams: Emergency Action Plans & Post-Irene Engineering Services

Windham, New York

C.T. Male Associates was hired by the Batavia Kill Watershed District to prepare Emergency Action Plans for their three dams in the Town of Windham.  Built in the 1970’s as flood control structures, all three dams are categorized as Class “C” (High Hazard) dams by  New York State Department of Environmental Conservation (NYSDEC).  Pursuant to NYSDEC Dam Safety regulations and the District’s request, Emergency Action Plans (EAP’s) were prepared for each dam in accordance with NYSDEC, Natural Resources Conservations Services (NRCS) and Federal Emergency Management Agency (FEMA) standards.  Included within the EAP’s were notification flow charts, procedures for emergency responders to follow, and a list of affected downstream property owners.

The severe rainfall experienced from Tropical Storm Irene resulted in significant flows through the auxiliary spillways of these dams.  During this event, these earthen spillways were suffering extensive erosion and prompted the Town to activate their Emergency Action Plans for fear that the erosion could lead to failure of the dams.  As the Engineer-of-Record, C.T. Male Associates visited the site during the storm to assess the conditions and to work with local authorities in enacting the EAP.  Upon recession of the floodwaters, each of the dams’ low-level drains were opened to increase storage capacity and reduce the likelihood of further flows through the auxiliary spillways.

C.T. Male Associates was retained by the District to provide engineering services associated with restoration of the dams’ auxiliary spillways.  The extents of the erosion were mapped by a C.T. Male survey crew using a Leica ScanStation HDS 3600 high definition LIDAR (light detection and ranging) laser scanner.  After consultation with NYSDEC, permits were issued for performing emergency repairs to the dams in the fall of 2011.  Preliminary plans and specifications for emergency repairs were prepared by C.T. Male and emergency restoration work proceeded until winter shutdown in December 2011.  Final project plans and specifications were then prepared for complete restoration of the auxiliary spillways in the spring of 2012 which incorporated the use of turf-reinforcing mats to stabilize the earthen spillway surfaces.  This work was completed in 2013.