Hudson Valley Federal Credit Union
Hudson Valley Federal Credit Union (HVFCU) planned to add a 50,000 square foot 2-story addition directly adjacent to an existing 2-½ story financial institution. Existing municipal potable water and sanitary service connections served the facility. No change was made to the design of the existing potable water supply service. The existing municipal sanitary sewer service required modification of the existing on-site system. No change was made to the existing sewer manhole connection.
The on-site sewage collection system combines the original on-site gravity sewer with a design for a new pressurized sewer system. The pump station was designed to replace the sewage ejector pump located in the existing building’s basement, and was designed conservatively to handle the site’s total sewage flow. The flow from the existing building that drains toward the existing ejector pump and the flow from the proposed building was designed to drain to a new centrally located pump station on the south side of the building.
The design of the pump station was located near the existing sewage ejector pump pit to allow for gravity inflow. The pump station’s forcemain connects to a new sanitary manhole located on the original on-site gravity sewer. The original 4” sanitary cleanout is replaced by the new forcemain connection manhole. In addition, the original 4” gravity sewer line on the north side of the building remains in use and discharges into the new manhole.
Sanitary flows from the completed project are domestic in nature and void of any industrial solid, hazardous, or toxic waste contamination. Storm flows are controlled by and within a separate system.
All piping was designed in accordance with the parameters set forth in the Great Lakes Upper Mississippi River Board of State and Provincial Public Health and Environmental Managers’ “Recommended Standards for Wastewater Facilities” (also known as “Ten State Standards”), the New York State Department of Environmental Conservation’s (NYSDEC) “Design Standards for Wastewater Treatment” and Dutchess County Department of Health (DCDOH) regulations.
The sewer pump station was located and designed to preclude flooding, and to allow safe means of access under all weather conditions. It provides dual Hydromatic, explosion-proof, submersible grinder pumps; model G2FX300 (3 HP), with 7” diameter impellers within a 5’ x 5’ (inside dimensions) pre-cast concrete wet well tank. The tank is waterproofed on the exterior surface with two coats of bituminous paint subject to DCDOH standards, and was hydrostatically tested as per The Town of Poughkeepsie requirements. Pumping system are equipped with alternating controls and sized for a discharge of 90.0 gpm at 18.0 feet tdh.
Each pump is a three-phase 460-volt with an electrical disconnect box located at the control panel. The control panel is mounted to a panel board adjacent to the pump station in a NEMA 4X enclosure. Each pump is fitted with the manufacturer’s standard cutter system and impeller. All electrical equipment was designed and installed to comply with the National Electrical Code requirements for Class I Group D, Division 1 locations.
Shut-off valves and check valves on the discharge side of the pumps are specified and are accessible for maintenance. Controls are specified to provide a lead/lag capability and an alternating maximum of 3 cycles/pump/hour for the pumps under maximum day flow conditions.
