By: Rob Burckley, Induron Technical Sales & Service Manager
Committed to ensuring its community has reliable and safe water supply, the City of Portage, MI launched a rehabilitation project on an integral component of its water supply infrastructure–a 750,000-gallon toro ellipse leg water tank. Over time, tanks can deteriorate due to various factors, necessitating rehabilitation efforts to maintain their functionality and efficiency.
About the rehabilitation project
The City of Portage hired Dixon Engineering as the project engineer and G&L Tank Sandblasting & Coating as the contractor. The team was challenged with a lengthy list of repairs and a short turnaround time as the City of Portage could only handle a max of 60 days of the tank being out of service. Plus, April in Michigan does not offer the best weather conditions.
Project details:
- 750,000 Toroellipse Leg tank 145′ HWL
- Full exterior blast and paint with Containment
- Interior Dry blast and paint
- Pit piping and foundation clean and paint
Repairs needed:
- Install a wet interior roof hatch.
- Extend the access tube from the wet interior platform through the roof.
- Replace the top platform.
- Remove the wet interior platform plate.
- Replace the connecting hardware on the spider rods in the wet interior.
- Replace the fill pipe insulation.
- Overflow discharge modification.
- Install a mud valve.
- Replace the fall prevention devices in the dry interior ladders.
- Install a wet interior ladder.
- Replace the ladder supports on the access tube ladder.
- Replace roof vent with a pressure vacuum vent.
- Replace the roof handrail and painter’s railing.
- Remove the roof mast and tripod.
- Install bowl rigging couplings.
- Weld a patch plate in the access tube.
- Replace the overflow deflector plate in the wet interior.
- Roof stiffener support replacement.
- Remove abandoned antenna control box and section of conduit on a leg.
- Install light fixtures in the access tube.
- Replace the aviation light.
- Change all light bulbs in the dry interior.
- Remove the wet interior light fixture.
However, equipped with the proper coatings solution, the team was able to successfully complete the job in the allotted time.
The coatings solution
The project team turned to Induron Protective Coatings for their coatings expertise and products. Taking into account the short turnaround time, the condition of the tank and the weather conditions in which the project would take place, Induron specified the following coating system to restore the interior and exterior of the tank.
Exterior: Four-coat Zinc/Epoxy/Urethane/Fluoropolymer System, including a zinc rich primer, two component epoxy, two component aliphatic urethane and a fluorothane finish.
Primer: Indurazinc MC-67 @2.5 – 3.5 mils DFT
Epoxy Intermediate: PE-70 Epoxy @2.0 – 3.0 mils DFT
Urethane Intermediate: Indurethane 6600 Plus LV @2.0 – 3.0 mils DFT
Topcoat: Perma-Gloss LV @2.0 – 3.0 mils DFT
TOTAL: 8.5 – 12.5 mils DFT
Lettering: “PORTAGE” in three locations on the tank: Perma-Gloss LV @2.0 – 3.0 mils DFT
Dry Interior:
Two-coat epoxy system to the rest of the prepared surfaces:
Primer: PE-70 Epoxy @ 3.5 – 5.5 mils DFT
Stripe Coat: PE-70 Epoxy @1.5 – 2.5 mils DFT
Topcoat: PE-70 Epoxy @ 3.5 – 5.5 mils DFT
TOTAL: 7.0 – 11.0 mils DFT
Three-coat epoxy system to the access tube and bowl:
Primer: PE-70 Epoxy @ 3.5 – 5.5 mils DFT
Intermediate: PE-70 Epoxy @ 3.5 – 5.5 mils DFT
Stripe Coat: PE-70 Epoxy @1.5 – 2.5 mils DFT
Topcoat: PE-70 Epoxy @ 3.5 – 5.5 mils DFT
TOTAL: 10.5 – 16.5 mils DFT
Wet Interior: Coating Repair System
Primer: PE-70 Epoxy @3.5 – 4.5 mils DFT
Topcoat: PE-70 Epoxy @3.5 – 4.5 mils DFT
TOTAL: 7.0 – 9.0 mils DFT
Pit Piping:
Primer: PE-70 Epoxy @ 3.5 – 5.5 mils DFT
Stripe Coat: PE-70 Epoxy @1.5 – 2.5 mils DFT
Topcoat: PE-70 Epoxy @ 3.5 – 5.5 mils DFT
TOTAL: 7.0 – 11.0 mils DFT
