Water Filter Controllers for USACE Locks and Dams

The Contractor shall provide five (5) custom programed Stager Controllers for the well-water filtration systems that are installed at the following Locks and Dams: LD2 (Hastings, MN), LD5 (Minnesota City, MN), LD5A (Fountain City, WI), LD7 (La Crescent, MN), LD9 (Eastman, WI).  These systems were originally designed, built and installed by Robert Hill Company in St Louis Park, MN.

The resulting contract is for the replacement of the controller units only. The U.S. Army Corps of Engineers (USACE) has no preference for brand, make, or model of the controllers provided they comply with the performance requirements listed below and integrate into the currently working system. Additional parts may be required to insure the system and new components are compatible. No adjustment in contract price will be made for failure to ensure component compatibility. 

The systems at all five sites incorporate four tanks on a balanced manifold.  Iron in the water is oxidized then filtered through backwashing filters.  Oxidation is accomplished with dissolved potassium permanganate injected into the water stream via a chemical feed pump.  The chemical feed pump is wired to operate with the well pump.   

The filters are four 30” diameter steel tanks.  The filter beds are composed of manganese greensand, a manganese coated glauconite capped with anthracite filter coal.  The four in-line tanks filter, until a set volume is treated, or a set period of time has passed.  The filters are then taken off-line and back-washed individually.  Following backwash, the filters are then returned to service.  Backwash is provided by the remaining tanks on-line, so there is no contamination in the lower distributor or lower layers of the filter bed. 

Stager Controller

• Complete Stager Module
• UL (or nationally accredited test lab) listed components. 
• 12-month parts and labor warranty.
• Components and spare parts must be available within 10 days.
• Electronic copies of schematics, program data and ladder diagrams must be provided prior to award for evaulation. 
• Programs start, stop and cycle time of back flush cycle for well water filtration system.
• Capable of controlling pump and up to four greensand tanks.
• Measures and displays flow which can be used to determine that system is working effectively.
• Water flow ranges between 0-100 GPM (gallons per minute).  Typical service flow rate is 75 GPM (@ 3.5 fps).
• Backwash Cycle: 

o First Stage: 8 GPM/Sq Ft o Main Wash: 15 GPM/Sq. Ft o Maximum Backwash Rate: 18 GPM/Sq. Ft o Backwash Flow Rate: 75 GPM o First Stage Flow Rate: 40 GPM o First Stage Duration: 2 minutes o Total Backwash Duration: 10 minutes

• Quantity of Five (5) units at locations listed.  
• Contractor Requirements

    Must have minimum of five years documented experience in well water filtration systems and satisfactory performance ratings in Federal rating systems.

Installation and Training

• Includes turnkey installation, integration, programming and training
• Includes Operator and Maintenance (O&M) Manual complete with schematics, recommended spare parts, and part numbers.
• Electronic copies of schematics, program data and ladder diagrams must be provided. 

Contractor Site Visits

• Interested contractors are encouraged to see the application prior to bidding on these controllers.
• Minimum 48 hours’ notice is required and is limited to maximum of two hours per site.  
• Availability for site visits is during work hours of Monday through Friday 08:00 – 15:00.