AGRU HydroCLICK rehabilitates potable water source for town

History

Frederiksted is the smaller of the two main municipalities on St. Croix and serves as the docking point for cruise ships to the island. The small town is home to historical buildings including the Customs House and Fort Frederik as well as sandy beaches, shops, and restaurants. In 2019, following a recent renovation to the Frederiksted waterfront, the city implemented plans to also rehabilitate water lines and the potable water tank that supplies the town and resupplies docked cruise ships. For years Frederiksted’s aging water system had plagued the town with discolored water and low water pressure.

Problem

The 100,000+ gallon potable water tank that supplies the town and resupplies cruise ships measures about 35 ft in diameter and reaches 15 ft in height. The tank has been a source of issues in the past, with its inner concrete protective coating deteriorating and requiring frequent reapplication. The Virgin Islands Water and Power Authority (WAPA) contracted Leumas Engineering to create a longer-term solution.

The project posed unique challenges. First, St. Croix is geographically isolated, requiring extra considerations for both product and personnel planning. Second, the planned rehabilitation occurred alongside disruptive events that led to unavoidable delays, including hurricane weather, Covid-19 pandemic, and shipping interruptions associated with the 2021 Suez Canal Incident. Finally, there were other internal tank structures in need of replacement.

Solution

Initially, the engineers considered using a PVC flexible membrane liner (FML). However, after careful consideration of the project scope, the engineer chose to use a more robust 4 mm thick high-density polyethylene (HDPE) concrete protective liner (CPL). HDPE’s strength, durability, weldability, and host of complementary products such as pipes and fittings were among the reasons for its selection.

After choosing the material, the engineering firm reached out to AGRU America with an inquiry about its HydroCLICK system. AGRU collaborated with Plastic Fusion Fabricators, a long-time AGRU fabricator and installer, to outline the project specifications and plan an installation. Plastic Fusion served as a subcontractor and worked closely with the lead engineer on the project.

HydroCLICK carries all the benefits of a product made with HDPE as well as carrying features specifically for tank rehabilitation, offering enhanced installation times. Furthermore, HydroCLICK could be fusion welded to other HDPE elements like the new pipe at the bottom of the tank that replaced an older iron pipe. Lastly, the tank installer had over 20 years’ experience working with related products by AGRU.

Outcome

While Ernie Heins and Jeremy Harrelson at AGRU America served as the project coordinators on the manufacturing side, AGRU’s headquarters in Bad Hall, Austria oversaw product shipping. AGRU took care of all product organization, shipping the product as rolls and panels for on-site fabrication by Plastic Fusion Fabricators technicians.

Once the product arrived on-site, the installers prepared the tank by removing old steel ladder rungs, cleaning off the worn coating, and replacing the iron pipe at the bottom of the tank with HDPE pipe. Plastic Fusion techs then fabricated HydroCLICK into sections for installation, extrusion welding them together inside the tank.

After successfully completing the installation, the installers referenced the product’s ease of use and the lead engineer’s professionalism as positive factors. The client was satisfied with the outcome of the project and has been looking at other tanks that may need rehabilitation.