St. Charles Communities Pumping Station 7 – New Wastewater Pumping Station & Force Main

Key Accomplishments

Johnston Construction Company

• Johnston Construction Company’s scope included field investigations, coordination with the local electrical utility, new transformer and service coordination, connection to existing sewers, excavation, construction, testing, startup, training, O&M manuals, and turnover of the new pumping station.
• Major utility work included installation of approximately 3,245 linear feet of 16-inch force main, pigging of the new force main, approximately 1,795 linear feet of 14-inch gravity sewer, approximately 15 linear feet of 18-inch gravity sewer, and approximately 617 linear feet of 24-inch gravity sewer.
• The project required careful coordination with Charles County Department of Utilities to minimize interference with existing operations, coordinate temporary shutdowns, provide bypass pumping or vacuum truck support when required, and complete tie-ins without interrupting service.
• Johnston Construction Company served as the contractor for St. Charles Community, LLC on the St. Charles Communities Pumping Station 7 project in Charles County, Maryland. The project was designed by Whitman, Requardt and Associates, LLP and constructed to provide a new wastewater pumping station serving future development within the St. Charles Communities area.
• The work consisted of constructing a new submersible wastewater pumping station, including the pump station structure, screen facility, generator facility, process piping, valves, fittings, electrical systems, instrumentation, controls, telemetry, site work, utility piping, and related appurtenances. The station was constructed south of the proposed Gleneagles South development in Waldorf, with access at the intersection of Torrey Pines Drive and Continental Drive.
• The project included significant civil and utility construction. Major bid items included the new Wastewater Pumping Station 7 facility, installation of a new 16-inch force main, pigging of the new force main, construction of new 14-inch, 18-inch, and 24-inch gravity sewer, and shutdown coordination. The project also included erosion and sediment control, access coordination, site restoration, traffic control, and work necessary to protect existing facilities and adjacent utilities.
• The electrical, instrumentation, and controls scope included emergency power generation, automatic transfer switches, surge protective devices, grounding and bonding, raceways, ductbanks, wire and cable, panelboards, motor starters, low-voltage switchboard, transformers, lighting, lightning protection, electrical field acceptance testing, general instrumentation and control, process control systems, control panels, telemetry, and related startup and testing.
• Before substantial completion, Pumping Station 7 had to be online and operating after successful tie-ins, startup, station demonstration, testing, County personnel training, approved O&M manuals, and as-built drawings. The operational demonstration required the station to operate trouble-free for 14 consecutive calendar days with flow temporarily diverted from the Stadium Pumping Station to Pumping Station 7.
• The Project Was Completed On 31st December 2018

Concrete Services Division

• Concrete Services Division, LLC performed concrete placement, forming, finishing, and curing work for the St. Charles Pumping Station 7 project in Waldorf, Maryland.
• CSD’s scope included structural concrete work associated with the new pumping station facility, including generator pad, transformer pad, pump station building wet well, screen room, pipe room, grade slab, canopy piers, and housekeeping pads.
• Major work included formwork, concrete placement, concrete finishing, concrete curing, reinforcing steel support, anchor bolts, sleeves, embeds, expansion joints, vapor barrier, waterstop, premolded joint material, and concrete accessories.
• CSD performed concrete work for the pump station wet well, including wet well slab, wall sections, wall openings, concrete fill, pipe fillets, lower fillets, top fillets, and related wall and slab placements.
• CSD performed concrete work for the screen room and pipe room, including slabs, walls, beams, pipe room beam, electrical room recess, top fills, wall openings, and fiber reinforced concrete fill.
• The work required coordination with Johnston Construction Company, Charles County standard specifications, structural drawings, architectural drawings, mechanical drawings, approved shop drawings, concrete suppliers, reinforcing steel suppliers, concrete pumping services, testing laboratory, and overall project sequencing.
• Concrete Services Division, LLC performed the concrete placement and structural concrete scope for the St. Charles Pumping Station 7 project in Waldorf, Maryland. The work was completed under subcontract to Johnston Construction Company for Job No. 2014-04.
• The project included concrete work associated with construction of the new St. Charles Pumping Station 7 facility. CSD furnished labor, material, tools, forming, placement, finishing, and curing services necessary to complete the concrete scope in accordance with the subcontract documents, contract documents, structural drawings, architectural drawings, mechanical drawings, Charles County standard specifications, and project requirements.
• CSD’s work included concrete items for the generator pad, transformer pad, pump station building wet well, screen room, pipe room, grade slab, canopy piers, and housekeeping pads. The scope also included sidewalks by others, but CSD was responsible for concrete placement coordination and work shown in the subcontract scope.
• The generator pad work included frost walls and slab placement. The transformer pad work included frost walls and slab placement. CSD coordinated layout, formwork, placement, finishing, curing, and related accessories required for these equipment pads.
• The pump station building wet well work included wet well slab, multiple wall placements, wall openings, concrete fill, pipe fillets, lower fillets, top fillets, and related forming and concrete placement. This work required careful sequencing with reinforcing steel, embeds, wall penetrations, pipe openings, and other structural and mechanical coordination.
• The screen room work included slab placement, multiple wall placements, wall openings, center concrete fill, top fill placements, and fiber reinforced concrete fill. CSD coordinated formwork, placement, finishing, curing, and related concrete accessories for these areas.
• The pipe room work included slab placement, wall sections, gutter formwork, sump formwork, bottom step, landing pedestal, grade slab, wet well beam, screen room beam, pipe room beam, monorail pedestals, and electrical room recess. This scope required coordination with structural openings, embedded items, and equipment support requirements.
• Additional concrete work included canopy piers, housekeeping pads for dehumidifier, service entrance switchboard, automatic transfer switch, MDS switchboard, transformer, and related mud mats. The work also included flowable fill between wet well wall and sheeting, flowable fill between screen room wall and sheeting, and concrete between slab and sheets.

B & R Electrical Contractors

• B & R Electrical Contractors, Inc. performed electrical work for the temporary pump manhole electrical scope on the St. Charles Pumping Station 7 project in Waldorf, Maryland.
• BRE’s scope included electrical work associated with the temporary pump manhole system, including temporary pump station controls coordination, conduit, wire, connections, CT cabinet, main circuit breaker, grounding, trenching, backfill, and electrical permitting.
• Major work included plywood backboard installation, conduit installation, wire and connection work, PVC conduit below grade, rigid metal conduit on exposed work, new CT cabinet, main circuit breaker, grounding of equipment and support rack, and trenching and backfill for conduits.
• BRE coordinated with the temporary pump station control panel, pumps, cellular dialer, automatic transfer switch, and control panel supplier for packaged pump station control equipment.
• BRE provided shop drawing and O&M manual review support, coordinated material delivery, coordinated temporary electrical service work, and provided as-built / record drawings upon project completion.
• The work required coordination with Johnston Construction Company, Southern Maryland Electric Cooperative, equipment suppliers, temporary pumping requirements, electrical permit requirements, and overall project sequencing.
• B & R Electrical Contractors, Inc. performed the electrical subcontract scope for the St. Charles Pumping Station 7 project in Waldorf, Maryland. The work was completed under subcontract to Johnston Construction Company for Job No. 2014-04.
• The project included electrical work associated with the temporary pump manhole and temporary pumping requirements for the St. Charles Pumping Station 7 project. BRE furnished labor, materials, tools, supervision, and electrical services necessary to complete its scope in accordance with the subcontract documents, contract documents, project requirements, and electrical code requirements.
• BRE’s work included installation of a plywood backboard for electrical equipment, conduit, wire, and connections. The conduit scope included PVC conduit below grade and rigid metal conduit for exposed work. BRE also provided the new CT cabinet and main circuit breaker required for the temporary pump manhole electrical service.
• Electrical grounding work included grounding of equipment and the support rack. BRE also performed trenching and backfill as required for conduits from the transformer to the backboard and from the backboard to the temporary pump manhole.
• BRE coordinated the temporary pump station control equipment, including the temporary pump station control panel, pumps, cellular dialer, automatic transfer switch, and control panel supplier. The subcontract required coordination with the packaged pump station control equipment supplier and related temporary pumping components.
• BRE’s scope included coordination with Southern Maryland Electric Cooperative, electrical permit support, shop drawing and O&M manual review, material delivery coordination, and field coordination with Johnston Construction Company.
• The work also included as-built / record drawings upon project completion and per diem / travel as required by the subcontract. BRE coordinated with JCC’s project schedule, planning meetings, delivery requirements, and field sequencing to support the temporary pumping work.
• The project required careful coordination of temporary electrical service, control equipment, conduit routing, grounding, electrical inspection, utility coordination, and startup support so the temporary pump manhole electrical system could support the overall Pumping Station 7 construction sequence.