Tata & Howard is providing engineering services to the Grafton Water District for the Trinity Avenue Pump Station at the Trinity Avenue Wellfield. The project included permitting, design, and bidding of the pump station as well as providing assistance with permitting, design, and reporting to the Massachusetts Department of Environmental Protection (MassDEP) for the proposed Trinity Avenue Well site. The property was owned by the Massachusetts Division of Fisheries and Wildlife (DFW). The Grafton Water District swapped land with the DFW to obtain ownership and control of the Trinity Avenue site. Test wells were installed and short term pump tests were completed on each of the wells. Based on the results of the tests, it was recommended to install a three well configuration of 18 inch x 12 inch gravel packed wells resulting in approximately 800 gallons per minute (gpm). The project included an evaluation of alternatives for the access road including installation of a bridge or an open bottomed culvert, and T&H assisted with the preparation of permanent easements for the installation of utilities and roadway to the well site. In addition, T&H prepared and submitted an NOI to the Grafton Conservation Commission. Design included double wythe block and interior concrete painted block with wood truss roof and asphaltic shingles; and security included chain link fence, gates, locks, intrusion alarms, and lighting. T&H also assisted with the coordination of the installation of three phase power to site. Chemical feed at the station includes KOH for pH adjustment and chlorine gas for disinfection. Standby power was included in an outdoor enclosure. The design also included a 24-inch transmission main for 4-log removal. Currently, T&H is providing construction administration and resident observation services.
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.
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. The 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.
Tata & Howard provided design and construction services for a new water treatment facility that houses a 1.2 mgd ultrafiltration system and completed a pilot test that consisted of an evaluation of two separate ultrafiltration technologies. Franklin Wells No. 1 and 2, located off Hayward Street in Franklin, Massachusetts were installed in the 1940’s with a combined safe yield of 1.2 million gallons per day. Due to high concentrations of iron and manganese in the groundwater, the wells were only used to meet peak water demands during the summer months. The construction of the water treatment facility recaptures the yield from these two sources. The water treatment facility consists of a main building which houses static mixers, ozone feed equipment, chemical feed equipment, prefilters, membrane filtration equipment, instrumentation and controls. Treatment consists of ozone oxidation followed by membrane ultrafiltration. The project was funded in part by the Massachusetts Water Pollution Abatement Trust through a low interest state revolving fund loan.
The overall treatment scheme is as follows: ozone injection, oxidation of iron and manganese in an ozone contact tank, prefiltration, treatment through two ultrafiltration membrane skids, chlorination prior to a clearwell, and fluoride addition prior to discharge into the distribution system. The plant is designed to recycle backwash water and membrane recirculation water to the head of the plant utilizing two decant tanks. Ozone is produced on site utilizing compressed air, while a LOX tank is available to allow for the production of additional ozone if required in the future.
Tata & Howard provided design of 1,400 linear feet of 12-inch diameter water main on Griffin Street, High Street, and Stewart Street. Work included the preparation of design plans and specifications, hydraulic modeling to determine main size, and letter and cost estimate to the Palmer Community Development Department. Tata & Howard also provided construction administration and resident observation services. The project was funded by a USDA Rural Development Community Development Block Grant (CDBG).
Upgrade for a 750,000 gallon per day extended aeration wastewater treatment facility to an A/O biological facility. Assistance included acquiring State CWSRF planning grants and USDA Rural Development grant for extensive improvements including separation of combined sewer/stormwater collection systems (CSO), advanced Class A sludge treatment, and reconstruction of original 1970’s treatment facility to new Anoxic/Oxic Treatment System. Total grant funds were $7,275,000.
This project included construction of a 1.5 mgd capacity water treatment facility to treat potable water pumped from the existing Deaconess Well. The water treatment facility consisted of six vertical LayneOx pressure filters. The work also included demolition of the existing well pumping station and construction of a well pump vault with vertical turbine pump over the existing well, and completion of a SCADA system design to monitor and control the water treatment facility and well station.
Faced with increasing iron and manganese concentrations at two of its existing wells, Concord Public Works (CPW) decided that treatment was required. Several treatment options were evaluated, with the most cost effective option being pressure filtration. Piloting pitted manganese greensand against LayneOx, a proprietary media marketed by Layne-Christensen Company utilized in other parts of the country, but not in New England. In addition to proving its effectiveness in iron and manganese removal, “new technology approval” was obtained for the media from MassDEP. Although piloting showed LayneOx to have an advantage over greensand during testing at the Deaconess well site, the Town’s Procurement Office was reluctant to allow CPW to solely specify a proprietary media. Differences in piping and chemical requirements for both filter processes precluded a design that could have served either treatment system. Hence, a pre-purchase equipment bid was developed specifying both systems.
An additional challenge to treating the water was designing the treatment facility itself, whose architecture had to “blend in” with the bucolic and well healed character of the surrounding neighborhood. The Town requested that we provide three options simulating different themes; a barn, railroad station and a Richardsonian Romanesque style structure similar to the Chestnut Hill pump station. Our Architect provided renderings of the three options along with estimated costs and lists of pros and cons. After several meetings and input from various interested parties the Town chose the barn theme.
Tata & Howard completed a test evaluation and design report for the Bomil Well site comparing ultrafiltration using ozone and chlorine dioxide as oxidants. The report also evaluated several coagulant aids to treat the organic color in the water. The design report became the basis for the 2.5 mgd water treatment facility designed by Tata & Howard. The facility uses membrane filtration with chlorine dioxide for treatment. Construction administration was also provided by Tata & Howard.
Iron and Manganese Removal Using Greensand Pressure Filtration
Tata & Howard conducted a Water Quality Study that reviewed the Town of North Attleboro, Massachusett’s corrosion control practices, and evaluated changes in quality, specifically the increased levels of iron and manganese. The manganese concentrations in these wells had consistently increased during the past decade. The pilot treatment study for manganese removal with greensand pressure filtration was conducted at the Kelley Wells 1 and 2 and was a success. Tata & Howard completed the design of the 2.0 mgd capacity treatment facility and provided engineering services during the construction of the facility.
The design included the installation of a SCADA system for monitoring and control of the treatment facility and two well pump stations. A second operator work station was installed at the remote Water Department office which allowed both monitoring and control of the treatment facilities from this remote site. In addition, the operator work station was linked to the existing Autocon SCADA system which continued to monitor and control the remaining water system pumping stations and storage tanks and provide tank level signals for the establishment of start/stop setpoint controls for the new treatment facility and associated wells.
Tata & Howard provided engineering services for design, preparation of a hydrologic and hydraulic report, two easement maps, design submittals for DOT review, construction administration, and resident observation for the rehabilitation of the Great Brook Stormwater Culvert under Cherry Street in Waterbury, CT. The project provided for the replacement of about 65 linear feet of the existing structurally deficient top to the Great Brook Stormwater Culvert under Cherry Street and adjacent private properties. The existing steel beams, corrugated metal arches, and bituminous concrete or concrete slabs forming the top of the culvert were removed and precast concrete beams were placed on elastomeric bearing pads to form the replacement culvert top. Additionally, about 50 linear feet of the existing eroded cobblestone bottom were removed to a minimum depth of 12 inches and replaced with reinforced cast in place concrete. Further, approximately 32 linear feet of undermined walls (16 linear feet on the west side and 16 linear feet on the east side) were excavated, with cast in place concrete placed below the existing culvert masonry walls. The interior culvert masonry walls within the project limits were also repointed. The work required the reconstruction of 30 feet of Cherry Street, the adjacent sidewalks, and approximately 750 square feet of a private gravel parking lot property. During construction, a water control system capable of conveying normal flow capacity of the Great Brook Stormwater Culvert at Cherry Street was maintained.
Trinity Ave. Chemical Feed Pump Station, Grafton, MA
Tata & Howard provided engineering services for permitting, design, and bidding of the 1.3 mgd chemical injection Trinity Avenue Pump Station at the Trinity Avenue Wellfield. The project included an evaluation of alternatives for the access road including installation of a bridge or an open bottomed culvert; assistance with the preparation of permanent easements for the installation of utilities and roadway to the well site; preparation and submittal of an NOI to the Grafton Conservation Commission. The design included an access road, bailey bridge with abutments, double wythe block building, interior concrete painted block with wood truss roof and asphaltic shingles, installation of three (3) submersible pumps and pitless adaptors, approximately 1,800 linear feet of 6-inch and 12-inch water main, emergency liquid propane tanks and generator, instrumentation and controls, a SCADA system for the pump station and wells, and a 24-inch transmission main for 4-log removal. Security included chain link fence, gates, locks, intrusion alarms, and lighting. Tata & Howard also assisted Owner with the coordination of the installation of three phase power to site. Chemical feed at the station includes KOH for pH adjustment and chlorine gas for disinfection. Standby power was included in an outdoor enclosure. The project is currently under construction and is expected to be completed by the end of 2017.
Join Our Team
Tata & Howard is interested in motivated environmental professionals dedicated to providing great client service and high quality, efficient work. Please send your resume and cover letter to HR@tataandhoward.com.
Tata & Howard
67 Forest Street, Marlborough, MA 01752
MA | CT | NH | AZ