Memorandum

City of Lawrence

Utilities Department

 

TO:

David L. Corliss – City Manager

Cynthia Wagner - Assistant City Manager

Diane Stoddard - Assistant City Manager

FROM:

Dave Wagner – Director of Utilities

CC:

Mike Lawless – Asst. Director of Utilities

Philip Ciesielski - Asst. Director of Utilities

Dave King, Utilities Maintenance Superintendant

Alan Landis – Purchasing Specialist

Date:

July 26, 2011

RE:

Project Summary for Emergency Repairs to the Kaw Intake and Low Service Pump Station 2

 

Please include the following item on the City Commission Agenda for consideration at the September 6, 2011 meeting:

 

Authorize the City Manager to approve payment of the invoices from Cogent in the amount of $16,970 and Ace Pipe Cleaning in the amount of $20,000 for the Emergency Repairs to the Kaw Intake and Low Service Pump Station 2.

 

Background:

The lone intake to the Kaw Water Plant (KWP) lost the ability to draw water from the river twice this summer due to unknown causes. To date aggressive backflushing has eventually restored service. We do know there are significant amounts of sand in the Low Service Pump Station 2 (LS2). In addition, the KWP has been operating without the traveling debris screen in LS2 due to a failed gearbox and sand accumulation since July 1. The gearbox was repaired in mid July; however, the screen remains inoperable due to sand accumulation. Attempts to remove sand were partially successful but water demands required us to discontinue the effort and put the Kaw Plant back in service. Additionally the clarifier drive on the KWP presedimentation basin has failed and today it has been determined the drive is beyond repair. The KWP can remain in service under specific conditions without the presedimentation basin; however, treatment is more tedious and subject to upset or interruption. 

 

Because the river flows have been low there is currently little debris coming into the intake. We expect as the US Corp increases reservoir releases large amounts of grass, leaves, and other debris will come into the intake. It is critical that the traveling screen is operational when the releases begin; otherwise, we expect the intake to clog, likely causing flow restrictions or complete stoppage to the KWP.

 

Project Description:

Staff has been working on emergency procurement of equipment and services necessary to:

1) Remove the sand from LS2. 

2) Perform additional mechanical inspection of the traveling debris screen.

3) Facilitate more detailed inspection of the Kaw Intake structure at the river.

4) Concurrently to the above, provide a temporary water supply to allow the Kaw Water Plant to remain in limited production while performing repairs and evaluations.

5) Order and install a new presedimentation clarifier drive.

 

As we mentioned last week due to the emergency nature of this work we are proceeding to perform this work on a time and materials basis with qualified and available contractors working with City staff. It is estimated that the cost could exceed $100,000 for items 1-4. The basin clarifier drive is estimated at an additional $100,000. Please note cost estimates are very preliminary. Also, the scope of the work, depending on what is discovered, is variable.

 

Staff will provide a full report of the work performed at the completion of the project as well as request approval for payment of the services provided.

 

Project Status

On August 1, bypass pumping was placed in service to allow the cleaning of LS2 wet well and the repair of the traveling debris screen gearbox. Ace Pipe Cleaning completed the removal of about 1,500 cu.ft. of sand, silt, and debris from the wet well on August 2. The gearbox repair was completed on August 5 and the KWP was placed back in service. The bypass pump remained on site until the cleaning and inspection of the intake crib was completed on August 15. The following is a summary of the major expenditures associated with the cleaning and repair project.

 

1.    Ace Pipe Cleaning – $20,000 for two 12 hour shifts to remove sand, silt and debris

2.    Cogent (Lee Mathews) - $16,970 for 3 weeks pump rental with one 1 of the weeks at 24/7 operation

3.    Central States Underwater Contracting - $4,850 for 3 man dive crew for 1 day of inspection and cleaning

4.    Elliot Equipment Co. - $5,212 for 6” piping and fittings to cleaning the LS2 wet well and the intake crib

5.    IBT - $4,800 for debris screen gearbox repairs

6.    Arnie’s Boat Sales - $3,536 for dock materials

7.    1,188 gallons of diesel fuel ($3.77/gallon) for the bypass pump during the week of operation.

 

In addition to the materials listed above there were overtime hours for maintaining fuel supply to the pump during continuous operation and miscellaneous purchases of wood, rope, air hose, etc. needed to complete the work. The total cost of items 1-6 is $55,368 plus fuel and other miscellaneous materials for a total project cost of about $60,000. This does not include any regular or overtime hours.

 

Project Funding:

This project will be funded from the Department of Utilities Operations and Maintenance budget for the Kaw Water Treatment Plant.

Action Request:  Staff recommends authorizing the City Manager to approve payment of the invoices from Cogent in the amount of $16,970 and Ace Pipe Cleaning in the amount of $20,000 for the Emergency Repairs to the Kaw Intake and Low Service Pump Station 2.