Liberty-Fairfield Pump Station
Butler County, Ohio

Malcolm Pirnie designed this 9 mgd finished water booster station with an architectural design that reflects the community's rural character. The station is equipped with standby power generation to assure reliability of pumping operations, high-tech electronic controls, sound mitigation and site security systems. To gain stakeholder buy-in, 3-D design was used to involve residents early in decision making. 

Alvarado Water Treatment Plant Flocculation/Sedimentation Basins
City of San Diego

Two new flocculation/sedimentation basins at San Diego's Alvarado Water Treatment Plant are a vital link to planned plant expansion and rehabilitation, providing 100 mgd of additional pretreatment capacity and incorporating design features to accomodate future ozone facilities. With significant input from city staff regarding equipment selection and operability of the residuals transfer facilities, Pirnie's innovative design concepts included a flexible, energy-efficient, gravity-based sludge removal system that accomodated the hydraulics of the plant's extremely long basins. The Pirnie team also overcame constraints of construction on an extremely tight site bordered by a lake and a fragile habitat. 

Canyon Lake Water Supply Project
Guadalupe-Blanco River Authority, Texas

Malcolm Pirnie, with HDR Engineering, Inc., developed a new water supply system that withdraws water from Canyon Lake, treats it, and distributes 10 mgd of potable water to wholesale customers that previously relied on groundwater. Through a contract with several entities, including the San Antonio Water System (SAWS), the system provides the first major source of surface water supplied to the SAWS distribution system with free-chlorine disinfection. The engineers developed a disinfection strategy that maintains compatible water quality and meets the more stringent disinfection byproducts (DBP) standards for surface water supply. The membrane water treatment facility includes coagulation and microfiltration for removal of total organic carbon, the precursors of DBPs, and also provides an absolute barrier to microbial pathogens for protection of public health. An uncommon feature of the system, constant rate operation, fully utilizes the customers' capital investment and, more importantly, minimizes the unit cost of the water delivered. 

Harriman State Park Water System Improvements
New York State Office of Parks

In response to recurring water quality problems at Harriman State Park, one of the Northeast's major recreational facilities, a Consent Order-mandated deadline gave just over a year to modify existing treatment facilities to assure a reliable water supply. This was a challenging assignment, with highly variable seasonal demands, an extremely tight schedule, difficult site conditions and numerous stakeholders. To comply, Malcolm Pirnie replaced older facilities at two plants with new ultrafiltration units featuring innovative submerged membrane technology with vacuum filtration—the technology's first installation in New York. Two other aging drinking water facilities were decommissioned and new facilities were designed and constructed, including seven miles of pipeline and a booster pump station, to accomodate water from a private water distribution company. The project preserves the park's fragile natural environment and was completed on time — ready to welcome visitors at the start of the 2006 Spring season.

Lee Hall Water Treatment Plant
Newport News Waterworks

Faced with an aging facility and anticipating new water treatment rules, Waterworks Director Brian Ramaley set a course a decade ago to stay ahead of the regulatory curve. The old treatment plant was replaced with a new, highly efficient 54 mgd facility incorporating advanced technologies — dissolved air flotation, ozone and biologically active granular media filtration — that improve the aesthetic qualities of the water while meeting emerging regulations for the protection of public health. Called a national model for safety, security and sustainability, this is truly a drinking water treatment plant for the 21st century. 

Optimizing the Energy Efficiency of UV Disinfection
City of Albany, NY

Exploring opportunities to increase effieciency of this promising technology, we conducted a study at Albany's Loudonville UV facility under a cost-shared research grant from the New York State Energy Research and Development Authority. The study evaluated actions from selecting different lamp technologies, operating strategies, and lamp factors during design to using the most appropriate "challenge" organism during validation testing. Results will help create more energy-efficient water treatment facilities that protect the public health and meet regulatory concerns. 

Upgrade of Flint Lake and Airport Water Treatment Plants
Valparaiso (IN) Department of Water Works

While upgrading its water treatment plant to meet increased demand, the city addressed a major safety concern — the use of toxic chlorine gas to oxidize iron and manganese in the plant's groundwater supply and to provide disinfection. Our design replaced the existing potassium permanganate and chlorine systems with safer sodium hypochlorite, and added new pressure filters — meeting water quality goals, reducing chemical costs, and greatly reducing the risk to the community of a toxic gas leak. 

Brooklyn-Queens Aquifer Water Treatment Pilot Plant
New York City Department of Environmental Protection

High-quality drinking water from the aquifer below the heavily urbanized streets of Brooklyn and Queens? This unique groundwater management project is a major step toward making that happen. It  included an innovative pilot testing program to identify cost effective treatment technologies that could handle difficult groundwater quality for the design and construction of the full-scale Station 6, a new 10 mgd groundwater treatment plant.

The project will also satisfy multiple goals. Groundwater pumping will help control neighborhood flooding problems, an abandoned community “eyesore” will be converted for public use, and integrating efforts with NYSDEC will accelerate groundwater cleanup at a local hazardous waste site. A multi-phase community outreach program convinced skeptical local residents and fostered collaboration with public officials and the community — the key to gaining public and regulatory approval.

Clearwater Renewable Resource Facility
Tucson Water

Tucson Water faced a complex problem: the need to reduce dependency on declining groundwater resources and comply with State law mandating the use of its renewable water resource, Colorado River water from the Central Arizona Project (CAP). Earlier introduction of treated CAP water into Tucson’s distribution system had caused "red water" problems and sparked a local law prohibiting its use, so the City conceived the $80 million Clearwater program for recharge/recovery of 60,000 acre/ft/yr of CAP water.

Sanctuary Springs Water Supply Development
Nestle Waters of North America

Charged with developing a new spring source for Nestle Waters of North America (NWNA) bottled water in Michigan, Malcolm Pirnie used an innovative "whole-watershed" strategy to identify and develop the ideally suited Sanctuary Springs location. Malcolm Pirnie exceeded State regulatory requirements, investigating potential impacts of withdrawal on water bodies and water users by simulating long-term effects of spring development, an approach to water supply never before used in Michigan. Not only does this project meet present needs, but, according to Brendan O’Rourke of NWNA, “This program will help us in managing the Sanctuary Springs site in an environmentally sound manner and will also expand understanding of regional water resources.” 

Stoneman Lake TMDL Modeling Study
Arizona Department of Environmental Quality

An innovative hydrologic modeling project has brightened the future of Stoneman Lake — one of Arizona’s only natural lakes — where heavy growth of submerged aquatic vegetation (SAV) violated State water quality standards for dissolved oxygen, contributed to fish kills and reduced the lake’s aesthetic value. With the lake designated as “impaired” waters under the Clean Water Act, Pirnie used three linked computer models to simulate watershed loadings and allocate a TMDL for nutrients — the first project to specifically model aquatic weed biomass. Pirnie’s cost-effective, non-traditional solution required minimal construction to improve water quality.

Restoring Water Clarity
Tucson Water

After long dependency on groundwater, Tucson’s hopes for a renewable water resource — Colorado River water from the Central Arizona Project (CAP) – were dashed when residents’ complaints of “colored” water caused by corroded pipes led to a ban on CAP water use. To restore water clarity and customer confidence, Pirnie worked with Tucson Water and local groups to create an innovative solution. First, corrosion pilot testing programs simulating actual distribution conditions identified the best treatment. Then CAP water, recharged into the aquifer, was blended with local groundwater and pumped directly into residents’ taps in volunteer neighborhoods — the first ever drinking water demonstration project of such magnitude. Citizens enthusiastically accepted the blended water, paving the way for scale-up for long-term implementation and, equally important, renewing trust between Tucson Water and the community.

Central Avra Valley Storage and Recovery Program
Tucson Water

A landmark $1.5 million pilot water recharge facility (CAVSARP) will prove the feasibility of Tucson's planned full-scale aquifer recharge program to harness Colorado River water from the Central Arizona Project (CAP) for high-quality drinking water, overcoming the corrosive effects of conventionally delivered CAP water on Tucson pipelines. The project consists of three expansive (60-acre total area) infiltration basins capable of recharging 15,000 acre-feet of CAP water each to the regional aquifer, the first stage of efforts to achieve state-mandated "safe yield" by balancing groundwater pumping with natural and artificial recharge. Using fast-track approaches and innovative materials, Pirnie engineers met time and budget constraints.

Lake Gaston Water Supply Project
City of Virginia Beach

The City of Virginia Beach is the largest jurisdiction in the Hampton Roads area and the second largest city in Virginia. During the 1970s and 80s, Virginia Beach experienced population growth, which placed a tremendous demand on the water supply system and droughts made it necessary to impose water conservation measures and mandatory use restrictions. This caused the city, as well as federal, state, regional, and other local agencies, to emphasize the search for an additional water source for Southside Hampton Roads. Numerous alternatives were evaluated by the city using the criteria of cost, environmental impacts, legal, political, and institutional issues, quantity, quality, and reliability.

Lake Gaston emerged as the clear choice as the additional water source for the city and its one-sixth partner, the City of Chesapeake.  Malcolm Pirnie was the principal technical consultant for design and construction of 60 mgd raw water intake and pumping station, and 60-in-diam, 76-mi-long pipeline to transport raw water from Lake Gaston to the Suffolk area.