Marshall Heights Pump Station and Reservoir Improvements

Key Accomplishments

Johnston Construction Company

• The new electrical building was installed on a cast-in-place concrete foundation and coordinated with the dimensions, penetrations, equipment clearances, and service requirements of the new electrical systems.
• The new booster-pump system included motors, discharge piping, valves, supports, instrumentation, equipment connections, and an integrated pump-control panel located within the new electrical building.
• Each pump replacement was coordinated within a limited 12-hour outage period to protect continuous water-production capability.
• JCC maintained continuous electrical power to the Marshall Heights facilities throughout construction, including temporary generation when required.
• Existing electrical circuits were transferred to the new electrical building before demolition of the obsolete pump-station electrical equipment.
• The electrical improvements included new grounding and bonding, raceways, boxes, transformers, panelboards, switches, circuit breakers, motor starters, transfer equipment, surge protection, lighting, and exterior LED lighting.
• A power-system analysis was performed to support safe and reliable operation of the modified electrical-distribution system.
• JCC coordinated installation of a new programmable control system for local pump operation and remote monitoring through the Town’s existing SCADA network.
• The upgraded control system used water-level information from the Marshall Heights storage tank to automatically start and stop the booster pumps.
• Radio communications transmitted tank-level, alarm, pump-status, and mixer-status information between the reservoir, pump station, and the Town’s Water Treatment Plant.
• The controls included local Hand-Off-Automatic pump selection, high- and low-level alarms, pump-status monitoring, and time-delay logic to prevent simultaneous pump starting.
• JCC coordinated the controls transition while maintaining the existing operating sequence and continuous pump-station service.

Concrete Services Division

• Concrete Services Division, LLC performed concrete construction, reservoir repairs, and protective coating work for the Marshall Heights Pump Station and Reservoir Improvements project.
• Installed and stripped slab-on-grade and special concrete formwork required for the new structures and equipment foundations.
• Coordinated reinforcing-steel placement, anchor-bolt setting, concrete deliveries, pumping services, testing, and construction equipment with Johnston Construction Company.
• Performed reservoir concrete sawcutting, controlled demolition, surface preparation, repair, patching, and disposal activities.
• Performed approximately 6,000 linear feet of sawcutting and approximately 97 cubic feet of hand demolition associated with the reservoir rehabilitation.
• Handled and disposed of approximately five tons of material generated by the concrete repair operations.
• Applied approximately 32,077 square feet of protective membrane coating to the reservoir surfaces.
• Coordinated scaffold rental, installation, access, and oversight required to perform reservoir repairs and coating work safely.
• Installed concrete accessories including premolded joint material, waterstops, caulking, and related components where required.
• Performed concrete floating, screeding, finishing, pointing, patching, curing, and winter-protection labor.
• Coordinated the reservoir work within the project’s limited outage period and alongside installation of new vents, access hatches, and submersible mixer equipment.
• Concrete Services Division, LLC performed the concrete, reservoir-repair, and protective-coating work associated with the Marshall Heights Pump Station and Reservoir Improvements project in Orange, Virginia.
• CSD’s work included forming and placing concrete for the foundation supporting the new precast electrical building. The building was constructed to house the upgraded electrical service, distribution equipment, pump controls, instrumentation, and communications systems serving the Marshall Heights facilities.
• Concrete work for the electrical building included slab-on-grade and special formwork, concrete placement, floating, screeding, finishing, curing, and installation of required accessories.

B & R Electrical Contractors

• B & R Electrical Contractors, Inc. performed the electrical construction required for improvements to the Marshall Heights Pump Station and Reservoir facilities.
• Furnished and installed the conduit, conductors, boxes, devices, supports, terminations, and electrical connections included in the project’s Division 26 work.
• Installed a new 400-amp electrical service for the new precast-concrete electrical building and associated pump-station improvements.
• Furnished and installed a current-transformer cabinet, utility meter, 400-amp service disconnect, and 400-amp high-voltage panelboard.
• Installed a 45-kVA transformer and 150-amp low-voltage panelboard for building and auxiliary electrical loads.
• Installed weather-resistant disconnects and combination motor starters for applicable outdoor and process equipment.
• Coordinated the installation and electrical connections associated with the project’s automatic transfer equipment.
• Furnished and installed interior and exterior lighting, switches, receptacles, branch circuits, and associated controls.
• Installed underground electrical ductbank using direct-buried construction outside roadway areas and concrete encasement beneath roadway crossings.
• Installed Schedule 80 PVC conduit for applicable exposed and underground raceways and galvanized rigid conduit for the exterior electrical service.
• Demolished and made safe existing electrical equipment within the original pump-station electrical building after operational circuits were transferred to the new service.
• Supported the project requirement to maintain continuous electrical power during construction and equipment transitions.
• B & R Electrical Contractors, Inc. performed the electrical construction for the Marshall Heights Pump Station and Reservoir Improvements project in Orange, Virginia.
• A major component of the work was establishing a new electrical service for the precast-concrete electrical building. The service equipment included a current-transformer cabinet, utility meter, 400-amp service disconnect, and a 400-amp high-voltage panelboard.

Additional project details

• JCC constructed a new precast-concrete electrical building adjacent to the pump station, based on a Smith-Midland Easi-Set Model 1012 or approved equal, with an approximate exterior size of 10 feet by 12 feet.
• This sequence allowed existing circuits to be transferred to the new electrical service before demolition of the obsolete electrical equipment within the original pump- station building.