Repairs & Rehab Archives

Barnstable, MA Maher WTP Upgrades

Tata & Howard provided engineering services for a completion of a pilot test proposal, pilot testing, and pilot test report to evaluate the use of granular activated carbon (GAC) to treat PFOS/PFOA, advanced oxidation to treat 1,4 dioxane, and LayneOx and greensand pressure filtration to remove iron and manganese from the source waters (Well No. 1, Well No. 2, and Well No. 3) at the existing Maher Water Treatment Plant. Pilot testing was performed, submitted, and approved by MassDEP in July 2017. The pilot test report was prepared and submitted in January 2018 to MassDEP.

Tata & Howard also provided engineering design, permitting, bidding, and construction services for the expansion of the existing Maher Water Treatment Plant. Upgrades include a new 90’ x 90’ pre-engineered metal building, GAC treatment, chemical feed upgrades, electrical upgrades at the existing plant including a new stand-by generator, and miscellaneous piping and site work. The new carbon filtration building include granular activated carbon (GAC) filters designed to remove PFAS. In addition to PFAS, the facility will include treatment processes to treat 1,4 dioxane and iron and manganese in the drinking water.

This project involved Massachusetts public construction laws and procedures.

HVWP Water Distribution and Storage Improvement Project

Background

Hooksett Village Water Precinct (HVWP) Phase I Water Distribution and Storage Improvement Project is the first of three major drinking water components of the RTIA Tax Increment Financing (TIF) District economic development initiative sponsored by the Town of Hooksett. The project consisted of the construction of 1,800 linear feet of distribution system improvements in the Vista Drive area, a new 0.40 million gallon capacity glass-fused-to-steel tank, and 350 linear feet of associated transmission main from Daniel Webster Highway to Main Street.

The Precinct has been partnering with the Town, Sewer Commission, local businesses, committees, residents and area developers to encourage TIF-based infrastructure projects. TIF can be used to fund improvements that benefit the whole community by attracting new development, revitalizing blight, and/or enacting quality of life projects. This can significantly expand the tax base and provide more or easier access to services for residents with less financial impact.

Project Details

Hydraulic modeling studies completed in 2020 as part of the Precinct’s asset management program showed that distribution improvements were needed in the Vista Drive area to relieve a bottleneck that was critically restricting flow from the existing Quarry Tank and nearby wells. The Vista Drive area water main replacement/extension was listed as a Top Priority in the Precinct’s March 2021 Asset Management Plan Update. This area is the closest and primary source of water and fire protection for the TIF District, and a direct connection to the area is imperative to efficiently transmit water to the TIF District.

The Thompson Comer Tank is critical to water system hydraulics, not only for fire flow purposes but also for redundancy, emergency resiliency, and operational flexibility. It is inextricably linked to the operation of the Quarry Tank and the TIF District. Unfortunately, it had deteriorated to the point where it needed replacement. The new, slightly larger capacity replacement tank allowed the Quarry Tank to be taken offline as needed for O&M or emergencies; provide backup storage for the TIF district; allow the Quarry Tank to operate at 100% capacity; and improve overall energy efficiency by increasing off-peak operations.

Replacement of the existing Thompson Corner Tank also served as the permanent action plan to address a Significant Deficiency outlined by the New Hampshire Department of Environmental Services (NHDES) in October 2020. The deficiency identified was severe deterioration of the coating on the inside and outside of the tank. NHDES required that funding be authorized by March 2022 and a tank construction contract be awarded by October 2022.

The cost to replace the Thompson Corner tank and install the Vista Drive area water main and associated transmission main was $2,464,000 and was funded by 2021-22 NH Drinking Water & Groundwater Trust Fund (DWGTF) and NHDES American Rescue Plan Act (ARPA) Funds.

And the Winner Is…

Each fall, the Granite State Rural Water Association holds a drinking water taste test at its Annual Operator Field Day and Exhibit. In fall 2024, just after the completion of the project, HVWP had the honor of winning the contest!

Since Hooksett Village Water Precinct won the water taste test contest at Granite State Rural Water Association Operator Field Day this fall, they were able to represent New Hampshire in the National Rural Water Association’s The Great American Water Taste Test, where they won second place out of 43 systems in the National Rural Water Association’s “The Great American Water Taste Test” in Washington D. C. in February 2025. Mike Heidorn, P.G., Superintendent, represented HVWP and accepted the award.

We are very proud of the collaboration and efforts of both HVWP and the Tata & Howard team for the incredible success of our partnership.

Meadow Walk Mixed-Use Wastewater Design / Engineering Services

Tata & Howard provided engineering services for final design and construction documents associated with the design of a wastewater treatment facility utilizing membrane bioreactor (MBR) technology for the 50-acre Meadow Walk development at 526-528 Boston Post Road in Sudbury, Massachusetts. The site is a former Raytheon engineering and R&D facility.

National Development / Avalon Bay mixed-use residential and retail development, Boston Post Road, Sudbury, MA.

Believing the site was well-suited for mixed-use residential and retail development, Sudbury selectmen and residents voted to approve zoning and development plans proposed by National Development and Avalon Bay. The site was in development for two years and is nearing completion. The project consists of several independent components, which collectively comprise a mixed-use development with new open space, retail, and restaurants as well as walkable access to adjacent retail, office, and other services along Boston Post Road. The project also included local roadway improvements, major upgrades to the streetscape and landscaping, wastewater treatment improvements, and improved water quality.

Tata & Howard was contacted initially to prepare studies of existing conditions and proposed modifications to enhance and then upgrade the wastewater facility and disposal area on the site. Additional out-of-scope changes included value engineered alternatives and additional design services. The existing wastewater treatment facility was over 25 years old and required increased discharge limits; conversion to an MBR system to achieve higher removal of BOD, TSS, TN, turbidity, and other wastewater constituents; additional treatment redundancy; upgrades to meet current Massachusetts Department of Environmental Protection (MassDEP) guidelines; increased groundwater recharge; odor control; replacement of old infrastructure with a new pump station, gravity lines, and force main; a change to mixed land/water use to result in wastewater generation that could be more efficiently treated at the new wastewater treatment facility; and a new leaching field.

Upgrades included infrastructure and a new leaching field.

Hemlocks Raw Water Pumping Station

Tata & Howard provided engineering services for design, bidding, construction administration, and resident observation to Aquarion Water Company for improvements to their existing Hemlocks Raw Water Pumping Station in Fairfield, CT. The project included refurbishing five 300 hp centrifugal pumps and motors, replacing the existing variable frequency drives (VFDs), installing new piping, check valves, and strainers for each pump.

Hemlocks Pumps — BEFORE improvements to the Hemlocks Pumping Station.

As this facility is a source of supply for Aquarion’s Main System, it needed to be kept operational throughout the construction. The sequence of work required a single pump to be taken off line; refurbished; reinstalled with new piping, VFD, and appurtenances; tested and placed back into service prior to the next pump being taken off line.

Hemlock Pumps — AFTER improvements to the Hemlocks Pumping Station.

Another important aspect of the project was to replace the existing strainers so that they were easier for the plant operators to clean as they get clogged with eels. To simplify maintenance, new stainless steel wye strainers with bottom access to the screens were installed on the suction side of each pump.

Chamberlain Highway Receives New Water Main Connections

The Chamberlain Highway in Meridan, Connecticut has 536 linear feet of new 16-inch ductile iron main and two new fire hydrants. After Tata & Howard completed several test pits to verify connection locations at each end of the new main, construction work started on May 3, 2018 with the installation of a 16” x 16” tapping sleeve and valve at the north end of the project. This existing water main at the north end connection was originally installed in 1894.

Work progressed south until the new main was approximately 50 feet away from the other connection point in West Main Street. Connections to the existing main in West Main Street was performed over a 36-hour period due to the complexity and amount of utilities around the service connection, including a live 24-inch water main five feet away and multiple telephone conduits located 6 inches above the replaced main. Tata & Howard personnel on site at all times to observe that work was in performed in accordance to the plans and specifications.

Following the completion of the Chamberlain Highway water infrastructure improvement project, work to replace two water mains on the state-owned bridge crossing Sodom Brook in Meridan will begin.

Air Piping Improvements – Flagstaff, AZ

Tata & Howard provided professional engineering design services to the City of Flagstaff, AZ for the replacement of three aeration units, as well as interior air piping improvements for the Rio De Flag Wastewater Reclamation Facility (WWRF). In addition, approximately 400 linear feet of existing air piping were replaced at the Rio De Flag WWRF. The exterior pipe was visibly leaking air. For technical and operational reasons, screw compressors were chosen over turbo blowers. Tata & Howard provided design services including preparation of plans, specifications, and bid documents for the installation of the new screw compressors.

The existing air flow exterior pipe gaskets had deteriorated with the heat of the existing compressed air to where the piping was a safety problem and was also wasting energy. Tata & Howard worked with the City to provide shop approvals and assisted the City’s inspector to ensure the project met the plans and specifications.

The existing blowers at the plant were 25 years old, had reached the end of their useful life, and did not ramp up and down with the wastewater flow. The new aeration units will flow pace with the changing incoming flow and saved the City enough electrical energy that it is projected to pay for the upgrade in eight years. The electrical power company (APS) offered a large rebate to reward Flagstaff for taking this energy and money saving opportunity.

Burbank Tank Rehabilitation – Millbury, MA

The Burbank Tank is a 110-year-old buried fieldstone tank located in Millbury, MA. Due to concerns from MassDEP on the age and condition of the tank, the Aquarion Water Company contracted Tata & Howard to provide design specifications and DN Tanks was selected as the tank rehabilitation contractor for installing shotcreting lining to the fieldstone walls, pouring a new concrete floor and removing pipes within the tank that are no longer in use. While the proposed work is not a structural fix for the tank, shotcreting the walls will reduce potential root intrusion, seal up areas of lost mortar, and reduce the potential for leakage. The rehabilitation was undertaken in early 2017 and completed in 8 weeks.

The Burbank Tank is the only storage tank in the water distribution system. Therefore, careful planning and evaluation of the system using the hydraulic model was required to review the options for operations without storage for an extended period of time.

Canaan, VT and Stewartstown, NH Energy Efficient Wastewater Treatment Plant Upgrades

The Towns of Canaan, Vermont and Stewartstown, New Hampshire operate a shared wastewater treatment facility, which required significant upgrades. The existing facilities were 40 years old and although a few upgrades were performed in the 90s, the facilities were not performing well, did not meet Life Safety codes, and required significant maintenance. The upgrade met all of the goals of the Client by providing for simple operation and maintenance requirements, meeting the Life Safety codes, eliminating confined spaces, lowering of electrical power costs, and meeting discharge parameters through production of high quality effluent. The solutions developed for the upgrade to this facility were also economical.

Control building insulated concrete forms

One of the primary elements of the design was the consideration of the economics of energy reduction. The design incorporated insulated concrete form construction for the building walls with R-49 insulation rating in the ceilings. The design also included a wood pellet boiler with a pellet silo and hot water heating system, which allowed for reduction of explosion proof heaters in the headworks building. All of the windows were low-E and highly insulated, and an outer glassed-in entry way increased the solar gain retention of the building and reduced heat loss. he process headworks and operations buildings were constructed as single story structures, increasing operator safety.

The lagoon aeration system is now a fine bubble, highly efficient process with additional mixing provided by solar powered mixers that help reduce aeration requirements, improve treatment, and allows for the addition of septage, all at no cost due to solar power. The pump station upgrades were designed to eliminate daily confined space entry by the operator by the conversion to submersible pumps. For sludge removal, a unique and simple “Sludge Sled” system was incorporated, which allows the operators to easily remove the sludge at their convenience. Sludge treatment is accomplished with a geo-bag system that allows the sludge to be freeze dried, reducing the volume by almost 50% with no energy consumption.

The influent pump station was designed with three pumps instead of the normal two-pump system in order to meet both present and future design flows, allow for lower horsepower pumps, improve flexibility, reduce replacement costs, and reduce energy costs. The other four deep dry pit pump stations were converted to wet wells and submersible pumps, eliminating confined spaces, and are equipped with emergency generators, eliminating the need for operator attention when power is lost.

The incorporation of highly energy efficient building components resulted in reducing annual operation and maintenance costs, which resulted in lower user rates and a more sustainable facility. All building components are virtually maintenance free. All of the equipment and processes were selected to reduce both annual and future replacement costs.

The treatment system is a 3-cell aerated lagoon system, and the solar powered mixers were installed to enable reduction of the aeration needs and horsepower during the summer months when septage is added. The aeration blowers, which are housed in insulated enclosures, reduce noise and were sized to allow for the addition of septage to the lagoons, which is not common in Vermont. The aeration blowers are controlled with Variable Frequency Drives (VFDs), which allow for greater operator control of aeration and provide energy cost savings. The operation is simple and safe for operators and others who need to maintain the facility and equipment. The design has provided flexibility to the operators and has resulted in an energy efficient, sustainable solution for this community.

Read the whitepaper here.

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Odor Control at Wastewater Treatment Plant, Lyndon, VT

The wastewater treatment plant in Lyndon, Vermont was experiencing excessive odor issues. The existing odor control system relied primarily on chemical treatment, which was difficult for the operators to manage. Tata & Howard’s project design consisted of a bio-filter with root mulch to remove the odors, which are primarily ammonia, that are generated from the Auto Thermophilic Aerobic Digestion (ATAD) sludge treatment vessels. The ATAD system is a system that results in class A sludge that can be spread anywhere as a fertilizer, and it reduced the annual volume of sludge produced at this facility by 65%. The new system includes fans that pull the air off the top of the ATAD unit vessels through a cool down water wash tank, which knocks down the ammonia, and then pushes the air through PVC piping up through the root bio-filter shown in the picture. The total cost was under $300,000, for which Tata & Howard procured the Town a 100% grant.

The second part of the design project included a nitrogen reduction system for the secondary aeration process that may be necessary in the near future. The design includes a recirculation pump system from the Anoxic zone back to the Oxic zone. The Contractor was T. Buck Construction of Maine.

Means Brook Reservoir Dam and Gatehouse Rehabilitation, Shelton, CT — Aquarion Water Company of Connecticut

Means Brook Dam before rehabilitation, April 2011

The Means Brook Reservoir Dam is a concrete gravity dam that was constructed on rock in 1916 in Shelton, Connecticut. The aging dam required repairs in to improve reliability and safety, modernization and rehabilitation of the gate chambers, and replacement of the deteriorated upstream and downstream faces of the dam and the crest, which were severely spalled and delaminated. Hydraulic, hydrologic, and structural studies had indicated that the dam would be overtopped by about 3.9 feet by the Probable Maximum Flood, and that the dam did not have sufficient stability factors of safety for this extreme loading condition. The dam reportedly overtopped by about four inches during the 1955 flood. In 1977, modifications were made to the dam including extension of the spillway to its current length of 100 feet, and construction of a 2.1-foot high concrete parapet wall along the upstream crest of the dam.

Means Brook Dam after rehabilitation, August 2015

Tata & Howard provided design and construction administration for the rehabilitation of the dam that included the following:

Concrete repairs to the crest and both faces of the dam:
- Deteriorated and delaminated shotcrete and concrete removed to sound concrete;
- Anchor dowels and reinforcing installed, and new concrete surfaces poured;
- Upstream face was resurfaced to a depth of about six feet below spillway, and the downstream face to two feet below grade;
- New concrete surface designed with a nominal thickness of 12 inches on the downstream face and six inches on the upstream face.
- Installation of rock anchors post-tensioned in holes drilled through the dam into the rock foundation to improve stability and provide adequate factors of safety for overtopping by the Probable Maximum Flood.
- Removal and replacement of one section of the spillway training wall, and removal and resurfacing of concrete on remaining walls.
Repairs and improvements to the gatehouse and chambers:
- Reshingling of gatehouse roof;
- New steel plate exterior door for additional security;
- Blocking up the existing windows;
- Replacement of antiquated electrical system;
- Replacement of both of the inoperable sluice gates and their appurtenances in the upstream gate chamber;
- Replacement of the former vertical brass ladders in the intake gate chambers with new fiberglass ladders, including a base for fall protection and retrieval system;
- Replacement of wooden stairs in the lower gatehouse with new aluminum ships ladder;
- Replacement of the pneumatically operated butterfly valve on the 30-inch service main in the basement of the lower gatehouse with an electrically operated butterfly valve that can be remotely controlled;
- Installation of an extension stem and electric operator;
- Replacement of the 8-inch chamber drain and 10-inch auxiliary outlet gate valves;
- Replacement of wooden hatches over floor openings within the gatehouse with aluminum grating with cover plates;
- Installation of chain link fence along portions of the spillway training wall for safety; and at both ends of the dam for security;
- Installation of galvanized steel pipe railings along the upstream and downstream crest of the dam for safety; steel pipe rails were chosen for the dam crest instead of chain link fence because the dam crest is subject to overtopping.

The project received a 2017 Excellence in Engineering Merit Award from the American Council of Engineering Companies, Connecticut. Read more here.

Services: Repairs & Rehab