Surface Water Treatment Plant Ground Storage Tanks Rehabilitation

PROJECT

Surface Water Treatment Plant (SWTP) Ground Storage Tanks Rehabilitation

ENGINEER

City of Kilgore Engineering Department

CONTRACTOR

Cherokee Painting & Sandblasting, Inc.  (Jacksonville, TX)

CONSTRUCTION COST

Original Contract Price:  $468,850.00
Change Order No. 1 - $25,300.00
Change Order No. 2 - $1,200.00
Current Construction Cost:  $494,150.00
 
An independent third party (Dunham Engineering) was hired to inspect the roof of the North tank and make recommendations for repairs for a cost of $5,000.00.
 
Change Order No. 1 added the following work: (1) weld the rafter ends to the center bearing plate and fill pits in the bearing plate; (2) install 2 additional roof vents;  (3) Added caulk to roof rafters for additional protection;  (4)  Reweld seams in the shell;  and (5)  install a cap on fill pipe to aid in draining.
 
Change Order No. 2 added the sealing of seams in the roof to prevent the ponding of water.

 

FUNDING SOURCE

Utility Fund

PROJECT LOCATION

The Project is located on Farm to Market 349 (FM 349) in Gregg County 1000 ft. east of the intersection of US 259 Business and FM 349.

PROJECT SCHEDULE

Notice to Proceed:  February 1. 2016
Substantial Completion: July 2, 2016
Final Completion: August 6, 2016

Change Order No. 1 added seven days for investigation of roof rafters.

PROJECT DESCRIPTION

The Work under this contract consists of the rehabilitation of two 1,000,000 gallon (32’H x 75’Ø) welded steel ground storage tanks. The rehabilitation consists of taking the tanks out of service, draining the water, and removing all debris from the interior. All interior and exterior paint shall be removed by blasting and disposed of according to applicable law.  The interior and exterior surfaces shall be painted with a 3 coat epoxy paint system. Select existing appurtenances shall be removed and replaced with new units including, but not limited to roof vents, access hatches, and interior ladders. The tanks shall be disinfected and placed back in service upon successful completion of laboratory testing. Each tank is to be completed individually with only one tank out of service at any time.

JUSTIFICATION

The Texas Commission on Environmental Quality issued a notice of violation during the 2013 compliance investigation for the paint and appurtenances not meeting current standards and in general disrepair.  All of the City's tanks are inspected on an annual basis.  One tank was built in 1974 and the other tank was built in 1994.  These are the last of the tanks to be rehabilitated in the last 7 years.  All of our tanks will be brought up to the most recent AWWA code.

PROJECT STATUS

As of June 22, 2016

Painting and repairs to the North tank has been completed.  The tank is being disinfected and is expected to be placed back in service the week of June 27, 2016.

As of April 22, 2016

Surface preparation and priming of North tank is nearing completion.  During blasting, we discovered that the roof rafters had experienced severe corrosion bringing into question their ability to support the roof in the future.  An independent  third party engineer (Dunham Engineering) was hired to make recommendations for repairs.  The repairs recommended were to weld the rafters to the center support column and install 2 additional vents to aid in air circulation which will slow future corrosion.  Additionally, the rafters will be caulked against the roof to prevent future moisture buildup.  These changes were incorporated into Change Order No. 1.  Steel plates in the center of the roof were also replaced.  Filling and repairs of pits and holes by welding are also nearing completion.

 

 

WORK IN PROGRESS PHOTOS