Backwash Tank Installation
Plumbing to the back wash tank, and associated air-gap and air-space was performed by a Wisconsin Licensed Master Plumber under Wisc Chapter 145.
Backwash tank installation at this Wisconsin indoor aquatic center was designed to safely manage high-flow commercial pool backwashing from two pools within the facility. All plumbing work was completed in full compliance with the Wisconsin Plumbing Code by a Licensed Master Plumber, providing a sanitary, controlled, and reliable way to handle large backwash volumes while protecting both staff and chemical storage areas.
As part of a larger commercial pool planning effort, Pool Envy® evaluated the existing drainage configuration, identified capacity issues, and recommended a properly sized backwash tank installation to accept the combined flow from both pools and route it to a more suitable drainage connection. This work was performed to address real operational concerns such as floor drains being overwhelmed, water spreading toward chemical storage, and housekeeping challenges during backwash cycles.
Backwash Tank Installation Project Background
The aquatic center operates two commercial pools with substantial turnover rates and routine backwashing requirements. The existing discharge relied on a small floor drain that was never intended to handle the combined flow from a 6-inch backwash line on one pool and an 8-inch line on the other. During backwash cycles, the drain could be overwhelmed, causing water to move across the mechanical room floor and creating potential slip hazards near chemical storage.
Pool Envy® was engaged to provide facility-wide aquatic planning and to execute targeted improvements. This backwash tank installation became a primary component of that plan, solving surge-flow issues and establishing a safer, more reliable discharge process that aligns with code expectations and real-world operating conditions.
Existing Conditions Before the Backwash Tank Installation
Prior to the backwash tank installation, the facility experienced the following issues:
- A floor drain sized for localized flows rather than large backwash discharges from two pools
- Backwash water occasionally spreading across the equipment room floor
- Increased housekeeping needs and moisture near chemical storage areas
- No dedicated receiving tank to manage high surge volumes during backwashing
- Operational inconsistencies whenever both pools required backwashing in close succession
Design Approach and Plumbing Code Compliance
The solution involved installing a correctly sized fiberglass backwash tank to accept the combined flow from both pools and route it to a properly sized drain connection. All work was completed by a Wisconsin Licensed Master Plumber in accordance with the Wisconsin Plumbing Code.
The design for this backwash tank installation focused on the following objectives:
- Ensuring the tank could handle simultaneous high-flow backwashing from both pools
- Creating a proper air-gap to eliminate cross-connection risks between pool water and the drainage system
- Routing discharge to a larger, more suitable drainage pathway capable of handling surge flow
- Positioning the tank away from chemical storage to reduce risk if a drain ever backs up
- Eliminating uncontrolled water flow across the mechanical room floor during backwash cycles
Installation Overview
The new backwash tank was installed to receive discharge from both the 6-inch and 8-inch backwash lines. Piping was configured to maintain proper separation and a compliant air-gap above the fiberglass grating. The tank then directs flow to an appropriate drainage connection, preventing floor flooding and maintaining compliance with plumbing code requirements during peak backwash events.
Installation sequencing was planned to minimize downtime for the facility. The team coordinated with operations staff to maintain safety around chemical storage, circulation equipment, and mechanical room traffic during demolition, placement, and tie-in work. The result is a backwash tank installation that functions effectively without disrupting daily operations.
Results and Operational Benefits
Following the backwash tank installation, the aquatic center now experiences several measurable benefits:
- Backwash water is captured in the tank instead of overrunning the existing floor drain
- Reduced risk of water reaching chemical storage areas and other sensitive locations
- Cleaner and safer walkable surfaces during and after backwash cycles
- Confidence that discharge volumes are being managed in accordance with Wisconsin Plumbing Code requirements
- A system capable of handling actual flow demands rather than relying on an undersized drain
Project Snapshot
- Location: Wisconsin indoor aquatic center with two commercial pools
- Scope: Backwash tank installation and drainage reconfiguration
- Compliance: Wisconsin Plumbing Code, installed by a Wisconsin Licensed Master Plumber
- Flows Served: 6-inch backwash line for one pool and 8-inch backwash line for the second pool
- Objectives: Surge-flow management, chemical safety, drainage improvement, and code compliance
Planning a Similar Backwash Tank Installation?
If your facility is experiencing drain backups, wet mechanical room floors, or uncertainty about whether your backwash discharge is properly sized, Pool Envy® can evaluate the system and provide licensed, code-compliant solutions.
To learn more about related commercial pool work, visit the schedule a Safety and System Evaluation to discuss backwash tank installation, filtration improvements, and plumbing corrections backed by proper licensing and documentation.
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