1 Scope
NOTE This standard governs the procurement, specification, factory assembly, and field installation of packaged pump and lift station assemblies that lift wastewater or stormwater where gravity outfall is not available or is cost-prohibitive. (1.1)
NOTE A packaged station is a factory-assembled unit furnished as a complete, pre-engineered package. (1.2)
NOTE The package comprises the wet well basin, pumps, internal discharge piping, guide-rail removal system, valve vault, level controls, control panel, ventilation provisions, and the connection points to the influent gravity sewer and the discharge force main. (1.3)
NOTE The scope of this standard begins at the influent gravity sewer connection to the wet well and ends at the force main connection flange at the station discharge. (1.4)
NOTE The force main pipe, fittings, thrust restraint, and discharge-end reconnection are site-utility work; this standard governs the packaged equipment assembly and its two connection points only. (1.5)
NOTE This standard applies to the following service types, each of which changes pump selection, basin material, and hazardous-area treatment. (1.6)
- Raw (unscreened) sanitary sewage, including domestic and commingled light-industrial waste.
- Screened or settled effluent downstream of a building treatment or interceptor unit.
- Stormwater and surface drainage where gravity discharge is unavailable.
NOTE Stormwater stations carry no sewage gas and are therefore not classified under NFPA 820; all other sizing, control, ventilation-airflow, and testing requirements of this standard still apply to them. (1.7)
NOTE The following work is excluded from this standard and is governed elsewhere. (1.8)
- Single-building sump pumps, sewage ejectors, and integral-basin grinder pumps: Sump And Sewage Pumps.
- Site gravity sewer mains, manholes, service laterals, and the force main pipe external to the station: Sanitary Sewer Systems.
- Upstream storm drainage piping, catch basins, inlets, and detention facilities: Storm Drainage.
- Potable-water pressure-boosting pump skids: Domestic Water Booster Pumps.
- Fire pump assemblies and fire-protection water supply: Fire Pumps.
- HVAC chilled-water, condenser-water, and hydronic circulating pumps: Hvac Pumps.
- Municipal wastewater treatment-plant process equipment and public right-of-way sewer extensions and force mains, which follow AHJ municipal design standards.
1.9 Station Configuration
NOTE The packaged station configuration shall be selected to match the design flow and the redundancy required by the Authority Having Jurisdiction. (1.9.1)
NOTE Configuration is the first decision because it cascades into basin size, panel logic, and the standby-power interface. A simplex station has no redundancy and is limited to small, low-consequence service; duplex (one duty, one standby, alternating) is the default for commercial and institutional service; triplex and larger stations serve campus and industrial flows with lead/lag/standby logic. (1.9.2)
1.9.3Station configuration shall be as selected below.
○ Simplex (single pump, no standby) -- small commercial / residential only
● Duplex (duty/standby, alternating)
○ Triplex (lead/lag/standby)
○ Quadruplex (multi-pump campus / industrial)
1.9.4Stations serving more than a single building shall be duplex or larger so that the station retains pumping capacity with one pump out of service.
1.9.5Simplex stations shall not be used where an overflow or backup would discharge sewage to an occupied building, a watercourse, or a public way.
1.9.6Pump type shall be selected for the service and solids loading of the station.
● Submersible solids-handling (non-clog) centrifugal
○ Submersible vortex (recessed) impeller
○ Submersible grinder
○ Dry-pit / vertical non-clog centrifugal
NOTE Submersible pumps in a packaged basin are the default for site lift stations; dry-pit configurations shall be used only where the design head, flow, or maintenance requirements justify the larger above-grade structure. (1.9.7)
2 Referenced Standards
2.1Equipment, materials, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
2.2Where referenced standards conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
NOTE The 10 States Standards are a recommended-practice design reference adopted by many state environmental agencies as de facto AHJ criteria; they are cited here for firm-capacity, wet-well-volume, cycle-time, and velocity design rules, not as a code. (2.3)
| Standard |
Title |
| ANSI/HI 9.8-2018 |
Rotodynamic Pumps for Pump Intake Design |
| ANSI/HI 1.1-1.2 |
Rotodynamic (Centrifugal) Pumps -- Nomenclature and Definitions |
| ANSI/HI 1.3 |
Rotodynamic (Centrifugal) Pumps for Design and Application |
| ANSI/HI 1.4 |
Rotodynamic (Centrifugal) Pumps for Installation, Operation, and Maintenance |
| ANSI/HI 11.6 |
Rotodynamic Submersible Pumps -- Hydraulic, Hydrostatic, Mechanical, and Electrical Acceptance Tests |
| NFPA 820 |
Standard for Fire Protection in Wastewater Treatment and Collection Facilities |
| NFPA 70 (NEC) |
National Electrical Code (Articles 430, 501, 700/701) |
| UL 508A |
Industrial Control Panels |
| UL 778 |
Motor-Operated Water Pumps |
| ASTM D3753 |
Glass-Fiber-Reinforced Polyester Manholes and Wet Wells |
| ASTM C478 |
Circular Precast Reinforced Concrete Manhole Sections and Tops |
| ASTM C443 |
Joints for Concrete Pipe and Manholes Using Rubber Gaskets |
| ASTM F714 |
Polyethylene (PE) Plastic Pipe (DR-PR) Based on Outside Diameter |
| AASHTO HS-20 (H-20) |
Standard Specification for Highway Bridges -- H-20 Traffic Loading |
| NEMA MG 1 |
Motors and Generators |
| IPC Chapter 7 / Section 712 |
International Plumbing Code -- Sumps and Ejectors |
| IAPMO/UPC Chapter 7 |
Uniform Plumbing Code -- Sanitary Drainage Systems |
| 10 States Standards |
Recommended Standards for Wastewater Facilities (GLUMRB) |
3 Submittals
3.1 Action Submittals
3.1.1The Contractor shall submit the following action submittals for review before fabrication:
- Product data for pumps, motors, and the control panel, with model designations, performance curves, and listing marks.
- A station pump curve overlaid on the calculated system head curve, showing the duty point and the firm-capacity operating point with the largest pump out of service.
- Wet well sizing calculations showing active storage volume, minimum cycle time, and starts per hour for each motor.
- Shop drawings of the basin, valve vault, piping, guide-rail system, and access hatches, with the NFPA 820 hazardous-area boundaries delineated.
- A control panel schematic and bill of material showing duty/standby alternation, overload and phase-loss protection, alarm outputs, and SCADA/BAS dry contacts.
- Electrical one-line diagram including the standby-power interface, transfer means, and conductor and conduit schedule.
☑ Pump, motor, and panel product data with listing marks
☑ Station vs. system head curve with firm-capacity point
☑ Wet well sizing / cycle-time calculations
☑ Basin, valve vault, and piping shop drawings with NFPA 820 zones
☑ Control panel schematic and bill of material
☑ Electrical one-line with standby-power interface
3.2.1The Contractor shall submit the following informational submittals:
- Factory test reports per ANSI/HI 11.6, including the hydrostatic basin test and the pump performance test.
- Manufacturer certification that the control panel is UL 508A listed and that pump motors are UL 778 listed.
- Hazardous-area classification documentation confirming explosion-proof or intrinsically safe equipment in classified zones.
- Field acceptance test plan and reporting forms.
☑ Factory test reports (ANSI/HI 11.6)
☑ UL 508A panel and UL 778 motor certifications
☑ NFPA 820 hazardous-area classification documentation
☑ Field acceptance test plan
3.3 Closeout Submittals
3.3.1The Contractor shall submit the following closeout submittals before substantial completion:
- Operation and maintenance manuals for pumps, motors, controls, and the level-sensing system.
- As-built drawings showing installed elevations, start/stop setpoints, and the alarm activation level.
- Manufacturer warranty documents for the station, pumps, and control panel.
- Record of the field acceptance test, signed by the Contractor and witnessed by the Engineer.
☑ O&M manuals for pumps, motors, and controls
☑ As-built drawings with setpoints and alarm level
☑ Warranty documents
☑ Witnessed field acceptance test record
4 Quality Assurance
NOTE The station shall be furnished by a single manufacturer that is responsible for the complete packaged assembly, including the basin, pumps, valve vault, controls, and their coordinated performance. (4.1)
NOTE Single-source responsibility prevents the split-scope failures that occur when basin, pumps, and panel are procured separately and no party owns the interfaces between them. (4.2)
4.3The pump manufacturer shall have produced submersible wastewater pumps of the specified type and size for not less than five years.
4.4The control panel shall be assembled by a UL 508A listed panel shop and shall bear the UL 508A listing mark.
4.5Pump motors shall be UL 778 listed for the service.
4.6Welding on steel structures and steel discharge piping shall be performed by welders qualified under a recognized procedure.
NOTE The manufacturer shall hold a pre-installation conference with the installing contractor to coordinate basin setting, anti-flotation, electrical service, and the standby-power interface. (4.7)
5 Environmental and Service Conditions
5.1 Hazardous Area Classification
NOTE Raw sewage and screened effluent wet wells generate hydrogen sulfide and methane and shall be classified and equipped in accordance with NFPA 820. (5.1.1)
NOTE The wet well interior and the space within 1 ft of every opening are Class I, Division 1; the space extending 3 ft to 5 ft around openings at grade is Class I, Division 2. This is the single most commonly omitted life-safety requirement in pump station specifications, and omitting it produces field RFIs and rework. (5.1.2)
5.1.3All electrical equipment located within the Class I, Division 1 wet well -- including level sensors, junction boxes, and conduit -- shall be explosion-proof or intrinsically safe and shall be installed with listed conduit seals at the boundary.
5.1.4Electrical equipment within the Class I, Division 2 zone around openings shall be rated for that classification.
NOTE Stormwater wet wells do not generate sewage gas and are not classified under NFPA 820; equipment in stormwater wet wells shall be rated NEMA 6P for submergence but need not be explosion-proof. (5.1.5)
5.1.6The hazardous-area boundaries shall be shown on the shop drawings and reconciled against the electrical equipment ratings before fabrication.
5.2 Ventilation
NOTE Classified wet wells shall be continuously force-ventilated to reduce the extent of the hazardous area and to limit hydrogen sulfide accumulation. (5.2.1)
NOTE Hydrogen sulfide is heavier than air and settles at the wet well floor; exhaust intake must therefore be drawn from the floor level, not the top of the basin. (5.2.2)
5.2.3Continuous ventilation shall provide not less than 30 air changes per hour, or 6 air changes per hour continuous plus 30 air changes per hour when the space is entered, in accordance with NFPA 820 and the 10 States Standards.
5.2.4Ventilation exhaust shall be drawn from the floor level of the wet well.
630
Default: 30 air changes/hour
5.3 Corrosion Protection
NOTE Raw sewage wet wells generate hydrogen sulfide that attacks concrete and steel; the wet well interior shall be protected against sulfide corrosion. (5.3.1)
NOTE Unlined concrete wet wells in raw sewage service deteriorate within five to ten years. Fiberglass and HDPE basins are inherently resistant; concrete basins require a protective lining. (5.3.2)
5.3.3Concrete wet wells in sewage or effluent service shall be lined with a 100% solids epoxy or polyurea coating applied to the manufacturer's specified thickness.
5.3.4Wet well interior coating shall be selected as below.
● 100% solids epoxy lining
○ Polyurea lining
○ HDPE / PVC liner sheet
○ Not applicable (fiberglass or HDPE basin)
6 Wet Well and Basin
6.1 Basin Material
NOTE The wet well basin material shall be selected for the service, depth, groundwater condition, and traffic loading of the installation. (6.1.1)
NOTE Fiberglass (ASTM D3753) is the most common packaged-unit basin and resists sulfide corrosion inherently. HDPE (ASTM F714) suits high-groundwater sites. Precast concrete (ASTM C478) suits large-diameter wet wells but requires a protective lining in sewage service. (6.1.2)
6.1.3Basin material shall be as selected below.
● Fiberglass (FRP) per ASTM D3753
○ HDPE per ASTM F714
○ Precast concrete per ASTM C478
6.1.4Precast concrete basin joints shall use rubber gaskets conforming to ASTM C443.
6.1.5The basin diameter shall be sized to house the selected pumps, guide rails, and level controls with the clearances required by ANSI/HI 9.8-2018.
6.2 Anti-Flotation and Structure
NOTE The basin shall be designed and ballasted to resist flotation under the maximum credible groundwater level with the wet well empty. (6.2.1)
NOTE A buried empty basin is buoyant; a flotation collar, anti-flotation ballast, or structural anchorage sized to the local water table prevents the basin from lifting out of the ground. (6.2.2)
6.2.3The basin and its top slab shall be designed for the burial depth and surcharge loads of the installation.
6.2.4Where the station is located in a paved area, a driveway, or any area where vehicle access is possible, all basin top slabs, covers, and access hatches shall be rated for AASHTO H-20 traffic loading.
NOTE Standard fiberglass basins are not H-20 rated by default; the traffic-rated cover and reinforced basin shall be specified explicitly where required. (6.2.5)
○ Pedestrian / non-traffic
● AASHTO H-20 traffic-rated
6.3 Access
6.3.1Access hatches shall be sized to allow removal of each pump on its guide rail without entering the wet well.
NOTE Access hatches over a classified wet well shall be gasketed and lockable and shall be coordinated with the hazardous-area boundary. (6.3.2)
6.3.3Hatch material shall be aluminum or stainless steel selected for the corrosive wet well environment.
7 Pumps and Hydraulic Design
7.1 Firm Capacity
NOTE The station shall provide firm pumping capacity: with the largest pump out of service, the remaining pump or pumps shall convey the design peak hourly flow. (7.1.1)
NOTE This is the governing rule of the 10 States Standards and of most state AHJs. A station sized only at total installed capacity, without checking firm capacity, will be rejected at permit review or redesigned after bid. (7.1.2)
7.1.3Pumps shall be selected so that the firm-capacity operating point falls within the manufacturer's allowable operating region on the pump curve.
7.1.4The design peak flow shall be established for the station.
7.1.5The total dynamic head shall be established from the static lift plus the friction losses of the discharge piping and force main.
7.2 Solids Handling
NOTE Pumps in raw sewage service shall pass solids without clogging, and non-grinder pumps shall provide a minimum spherical solids passage of 3 in. (7.2.1)
NOTE A 3 in spherical free passage is the municipal sewage benchmark for non-clog and vortex pumps. Grinder pumps macerate solids instead and are used for low-flow pressure-sewer service where a small-diameter force main is required. (7.2.2)
7.2.3Pump free-passage or grinder capability shall be as selected for the service.
● Non-clog, 3 in minimum spherical solids passage
○ Vortex (recessed) impeller, full solids passage
○ Grinder (maceration) for pressure-sewer service
○ Stormwater non-clog (debris passage)
7.3 Wet Well Volume and Cycling
NOTE The active wet well volume shall be sized to limit pump starts so that motors are not damaged by short cycling. (7.3.1)
NOTE Excessive cycling overheats motors and fails seals prematurely. The active storage between the pump-on and pump-off levels sets the minimum cycle time. The 10 States Standards limit starts to about 6 per hour for motors above 10 HP and about 12 per hour for smaller motors. The active volume in gallons is approximately V = Q / (4 N), where Q is the single-pump flow in gpm and N is the maximum starts per hour for one pump. (7.3.2)
7.3.3The active volume shall be calculated for the selected pumps and the maximum allowable starts per hour, and shall be confirmed in the sizing submittal.
7.3.4Maximum allowable starts per hour shall be as selected for the motor size.
7.4 Motors
NOTE Pump motors shall conform to NEMA MG 1 for insulation class, service factor, and enclosure rating, and shall be rated for continuous submerged operation. (7.4.1)
7.4.2Motor horsepower shall be established for the duty point.
7.4.3Motor supply voltage and phase shall be selected for the motor size and the available service.
○ 120/240V 1Φ (simplex, up to 2 HP only)
○ 208V 3Φ
○ 240V 3Φ
● 480V 3Φ
NOTE Single-phase 120/240V supply shall be used only for simplex stations with motors not exceeding 2 HP; motors above 20 HP shall be 480V 3Φ. (7.4.4)
8 Discharge Piping and Valve Vault
NOTE Each pump discharge shall be provided with a check valve and an isolation valve located in an accessible dry valve vault, not submerged in the wet well. (8.1)
NOTE Submerging valves in the wet well makes them unmaintainable and exposes them to sulfide corrosion and rag fouling. A separate dry valve vault is required so that valves can be inspected and serviced without entering the classified wet well. (8.2)
8.3A check valve shall be installed on each pump discharge to prevent backflow when the pump stops.
8.4An isolation (shutoff) valve shall be installed downstream of each check valve so that either pump can be isolated while the other remains in service.
8.5A pressure gauge and a discharge cleanout shall be provided in the valve vault.
8.6The valve vault shall be configured as selected.
○ Integral vault (cast into the basin assembly)
● Separate adjacent precast vault
8.7Internal discharge piping and guide-rail components in contact with wastewater shall be of corrosion-resistant material suitable for the service.
○ Ductile iron, interior lined
○ 304 stainless steel
● 316 stainless steel
8.8 Force Main Connection
NOTE The force main connection shall be a flanged or restrained-joint termination at the station discharge, delivered to the limit of this standard's scope. (8.8.1)
NOTE The discharge force main shall be sized so that the velocity is not less than 2.0 fps at average daily flow for self-cleaning and not more than 10 fps to limit water hammer. (8.8.2)
NOTE Velocity must be checked at average daily flow, not only at peak. An oversized force main that cannot reach 2 fps at average flow accumulates solids, grease, and sulfide, causing odor complaints and pipe corrosion. (8.8.3)
NOTE The force main pipe, fittings, thrust restraint, and discharge-end reconnection are outside this standard and shall be coordinated with
Sanitary Sewer Systems.
(8.8.4) 9 Level Controls
NOTE The level-control technology shall be selected for the reliability the service demands, not for lowest first cost. (9.1)
NOTE Tethered float switches are inexpensive but jam on rags and debris in raw sewage; sealed floats are more reliable; non-contact ultrasonic or radar transducers and bubbler systems are the most reliable and are preferred for municipal-grade duplex service. Specifying "floats or equal" in raw sewage invites the least reliable option. (9.2)
9.3The level-control type shall be as selected below.
● Submersible pressure transducer
○ Ultrasonic / radar (non-contact) transducer
○ Bubbler system
○ Sealed float switches
○ Tethered float switches (small simplex only)
9.4A high-water alarm float shall be provided as an independent backup to the primary level-sensing device regardless of the primary technology selected.
9.5Level sensors located in the classified wet well shall be intrinsically safe and installed with the required conduit seals.
9.6Pump start and stop setpoints and the high-water alarm level shall be field-set and recorded on the as-built drawings.
10 Control Panel
NOTE The control panel shall be a UL 508A listed assembly in a NEMA 4X corrosion-resistant enclosure of stainless steel or fiberglass, suitable for outdoor installation. (10.1)
NOTE A NEMA 4X enclosure resists the corrosive, washdown, and weather exposure typical of an exterior station. The panel houses the motor controls, the duty/standby logic, protection devices, and the alarm and telemetry outputs. (10.2)
10.3The panel shall provide automatic duty/standby alternation so that pump run time is equalized across the pumps.
10.4The panel shall provide a hand-off-auto (HOA) selector switch for each pump.
10.5The panel shall provide an elapsed-time meter and a run indicator for each pump.
10.6The panel shall provide motor overload and short-circuit protection for each pump in accordance with NEC Article 430.
10.7On three-phase services the panel shall provide phase-loss and phase-reversal protection.
10.8The panel shall provide a high-water alarm with an external audible horn and visual beacon.
NOTE The alarm notification path shall be coordinated so that an unattended station alarm reaches an operator; the panel shall provide dry contacts for connection to SCADA, BAS, or an auto-dialer. (10.9)
NOTE A local horn and light that no one hears at night is not a notification path. The alarm output must be tied to a monitored system. (10.10)
10.11The panel telemetry interface shall be as selected.
● Dry contacts to SCADA
○ Dry contacts to building automation system (BAS)
○ Cellular / telephone auto-dialer
○ Local audible/visual alarm only (small simplex)
10.12Enclosure rating shall be confirmed for the installation.
● NEMA 4X stainless steel
○ NEMA 4X fiberglass
11 Standby Power
NOTE Most AHJs require standby power for duplex and larger stations; the standby-power interface shall be specified explicitly to avoid a bid clarification. (11.1)
NOTE The specification frequently omits whether the station requires a generator receptacle with manual transfer, an automatic transfer switch, or an integral engine-driven generator. The interface, transfer means, and connection details must be coordinated with
Emergency And Standby Power.
(11.2) 11.3The standby-power interface shall be as selected for the station.
● Generator receptacle with manual transfer switch
○ Automatic transfer switch (permanent generator)
○ Integral engine-driven generator
○ None (overflow storage / AHJ waiver)
11.5The station shall be grounded and bonded in accordance with Grounding And Bonding and NEC requirements for the classified location. 12 Testing
12.1 Factory Testing
12.1.1The wet well basin shall be hydrostatically tested at the factory at 1.5 times the design head with no leakage before shipment.
12.1.2Each pump shall be performance-tested at the factory per ANSI/HI 11.6 to confirm the specified flow and head at the duty point.
12.1.3The control panel shall receive a factory functional test confirming duty/standby alternation, protection devices, and alarm outputs.
NOTE Factory test reports shall be submitted before the station is shipped to the site. (12.1.4)
12.2 Field Acceptance Testing
NOTE After installation, the station shall be operationally tested under field conditions to confirm correct control and alarm behavior. (12.2.1)
NOTE The field test confirms the start and stop levels, the alternator sequence, the high-water alarm activation level, and the alarm notification path -- the items that cannot be verified at the factory because they depend on the installed elevations and the site telemetry connection. (12.2.2)
12.2.3The field test shall confirm the pump start and stop levels at the installed elevations.
12.2.4The field test shall confirm duty/standby alternator sequencing across successive cycles.
12.2.5The field test shall confirm the high-water alarm activation level and the alarm notification to the monitored system.
12.2.6Where a discharge force main is within the station scope, it shall be air-tested at 5 psi for 15 minutes with no loss before commissioning.
12.2.7The field acceptance test shall be witnessed by the Engineer and recorded on the closeout submittal.
☑ Pump start/stop levels at installed elevations
☑ Duty/standby alternator sequencing
☑ High-water alarm level and notification
☐ Force main air test (5 psi, 15 min)
13 Installation
NOTE The station shall be installed in accordance with the manufacturer's instructions, ANSI/HI 1.4, and the approved shop drawings. (13.1)
13.3The basin shall be set plumb on a compacted, level bearing surface and ballasted before backfilling to prevent flotation.
NOTE Wet well intake geometry, minimum submergence, and floor clearance shall be installed in accordance with ANSI/HI 9.8-2018 to prevent vortexing and air entrainment. (13.4)
NOTE The intake design standard sets the minimum floor clearance (about 0.3 times the pump inlet diameter) and the minimum submergence taken from the pump curve; violating these draws air into the pump and reduces capacity. (13.5)
13.6Pumps shall be installed on the guide-rail system so that each pump seats on its discharge connection by gravity and can be removed without entering the wet well.
13.7Electrical raceways and conduit shall be installed per Raceways And Conduit, with conduit seals at every hazardous-area boundary crossing. 13.8The influent gravity sewer connection shall be made watertight at the basin penetration, and the connection to the upstream sewer shall be coordinated with Sanitary Sewer Systems. 13.9After installation the station shall be cleaned of construction debris before the field acceptance test.
14 Delivery, Storage, and Handling
14.1The packaged station shall be delivered with pumps, controls, and accessories protected from damage and from the weather.
14.2The basin shall be handled and lifted only at the manufacturer's designated lifting points.
14.3The control panel shall be stored indoors or under weather protection and shall be kept dry until it is mounted and energized.
14.4Pumps and motors shall be stored upright and protected from contamination until installation.
15 Warranty
NOTE The manufacturer shall warrant the complete packaged station against defects in materials and workmanship for not less than one year from the date of substantial completion. (15.1)
15.2The pump and motor warranty period shall be as selected for the procurement.
○ 1 year
● 2 years
○ 3 years
○ 5 years
NOTE The warranty shall cover the coordinated performance of the assembly under single-source responsibility, not the individual components in isolation. (15.3)
16 Spare Parts
NOTE The manufacturer shall furnish the spare parts and special tools needed to maintain the station through the warranty period. (16.1)
16.2Spare parts to be furnished shall be as selected below.
☑ One spare seal kit per pump model
☑ One set of spare level floats / sensor
☑ Spare control panel fuses and pilot devices
☐ One spare check valve flapper / disc
☐ Guide-rail lifting chain or cable
16.3A complete spare pump shall be furnished where the AHJ requires on-site redundancy beyond the installed standby pump.