Over the past 45 years, Hensel Phelps has delivered more than $3 billion worth of water and wastewater construction projects, completing over 750 projects nationwide. As we give back to the communities we build in, our commitment to water infrastructure is rooted in the belief that water is not just a resource but the cornerstone of a thriving community. Our recent projects, like the Wellington Water Treatment Plant Expansion, showcase our commitment to action.

Wellington Water Treatment Plant Expansion

One of our recently completed project achievements is the award-winning $35 million Wellington Water Treatment Plant Expansion. This project was crucial for supporting the Town of Wellington’s infrastructure, more than doubling its capacity from 2 million gallons to 4.2 million gallons per day. Hensel Phelps installed 6,500 feet of buried pipe and 2,500 feet of interior pipe. We also placed 680,000 pounds of rebar and 4,000 cubic yards of concrete, all while coordinating with 35 subcontractors. The expansion ensures Wellington can provide clean drinking water for its community and accommodate future growth.

Town of Windsor Wastewater Treatment Facility

Another notable project is the $17 million Town of Windsor Wastewater Treatment Facility – Biosolids Management Improvements Project. The Town of Windsor was experiencing rapid growth, which increased the demands for its biosolids handling system. The existing equipment was aging and inefficient, leading to operational challenges. Our project included the construction of new aerobic digesters and dewatering facilities, which relieved capacity constraints, met future biosolids handling needs, and reduced operating costs. As a result, Windsor now fills one truck with dewatered biosolids every three weeks, reducing truckloads by 93% annually and significantly lowering the carbon footprint and safety risks.

Our success on the Biosolids Project led to winning the next phase of work at the site: the $85 million Windsor WWTF Liquids Expansion. This project will expand the facility’s capacity to treat 6.3 million gallons per day, ensuring that Windsor can meet environmental standards and support its growing population. Our success also led Windsor to award Hensel Phelps the $16 million Headworks project, which will upgrade the existing facility and construct an adjacent Headworks facility to increase capacity. The new facility will house the new grit concentrators and fine screen effluent channels, as well as the new electrical and mechanical rooms.

Kailua Regional Wastewater Treatment Plant

Our successes in the water sector led us to Hawaii, where Hensel Phelps took on the $149 million Kailua Regional Wastewater Treatment Plant (KRWWTP) project. The project consisted of multiple critical facilities, including the Tunnel Influent Pump Station (TIPS), Mini Kailua Influent Pump Station, Generator/Electrical Distribution Building, Fuel Tank Pad, Headworks Facility, Sewer Pump Station and Force Main.

This comprehensive project also involves extensive utility and drainage system improvements. As part of the Kaneohe/Kailua Sewer Tunnel Project, it aims to efficiently convey wastewater flows from the Kaneohe Wastewater Pretreatment Facility to the KRWWTP, providing essential storage for peak wet-weather flows and mitigating overflow risks. The project won the 2019 GCA Build Hawaii Award.

Kaneohe/Kailua Tunnel Influent Facility

Staying in Hawaii, the Kaneohe/Kailua Tunnel Influent Facility, constructed at the Kaneohe Wastewater Pre-Treatment Facility, represents the third and final phase of the City and County of Honolulu’s Kaneohe-Kailua Wastewater Conveyance and Treatment Facilities project. The $21 million project comprised a 61,991-square-foot endeavor, including developing a new generator, electrical building, odor control facilities, and connecting underground pipelines and utilities. The facility boasts a complete, functional process control system (PCS) encompassing the supply, installation and calibration of the control system network, instrumentation and signal systems. The project also involved comprehensive structural finishing, mechanical, architectural, electrical and instrumentation work at diversion, drop structures, and junction structures for the new conveyance tunnel.

To comply with a U.S. EPA consent decree, Hensel Phelps played a crucial role in the tunnel work, installing fiberglass to seal ports and joints. This project, completed in 2018, earned the City and County of Honolulu the prestigious 2019 American Council of Engineering Companies People’s Choice & Grand Conceptor Award.

Waianae Wastewater Treatment Plant

As a focal point in the construction industry of Hawaii, Hensel Phelps constructed the $16 million Waianae Wastewater Treatment Plant (WWTP) project. The project involved the construction of a new No. 2 non-potable water (2W) piping network with isolation valves, rehabilitation of primary clarifiers and influent/effluent distribution boxes and piping, 2W seal water system improvements, new headworks influent screens and washer/compactors and modifications to the grit removal system and pre-aeration tanks. Hensel Phelps self-performed 75% of the work, including concrete repairs and installation, demolition, air ductwork, soil erosion and sediment control, electrical site work, temporary diversion pumping, and the start-up, testing and commissioning of systems. Although the main project has concluded, Hensel Phelps continues work at Waianae WWTP under a separate contract to replace the biosolids dewatering system.

Kuna East Water/Wastewater Infrastructure Project (WWIP)

Another project that wrapped up in 2024 was the $99 million Kuna East Water/Wastewater Infrastructure Project (WWIP) in Kuna, Idaho. This 182-acre development was built to support the East Kuna Industrial Overlay District, including the Kuna Data Center campus. The project required extensive mass excavation to accommodate a new 2-million-gallons-per-day water system featuring potable wells, a booster pump station and a 2-million-gallon storage tank. It also included a wastewater system capable of processing 270 gallons per minute through lagoons, lift stations and a reuse system that safely returns treated water to the environment. Designed with future expansion in mind, this scalable and sustainable infrastructure supports long-term industrial growth in the region.

Water Construction Forecast

A recent EPA survey highlighted that at least $630 billion will be needed to improve wastewater, stormwater and other clean water infrastructure over the next 20 years. With more than 16,000 wastewater treatment plants in the U.S. operating at an average of 81% capacity and 15% exceeding their design capacities, the need for infrastructure improvements is clear.

In addition, we were recently awarded the preconstruction contract for a project in the Rocky Mountains to remove per- and polyfluoroalkyl substances (PFAS) from the local drinking water supply. This project is critical due to a federal mandate to protect communities from harmful PFAS, known as “forever chemicals.” The U.S. Geological Survey estimates that at least 45% of tap water is contaminated with one or more types of PFAS. This project is among the first of its kind in Colorado and underscores our capability to tackle complex and pioneering initiatives.

Hensel Phelps is dedicated to addressing these challenges and providing innovative solutions to ensure a sustainable future for water. Paired with our ability to manage complex projects in the water and wastewater sector, clients can trust that we can be the perfect partner for the future of water infrastructure.

To learn more about our Water Projects and who to contact for project development, visit us here: https://www.henselphelps.com/contact-us/water/.