Sewer Feasibility Study and Sewer System Design — New Fairfield, CT  

Tata & Howard completed a Sewer Feasibility Study for the Town of New Fairfield, CT to determine the feasibility of developing a sewer service area for the Town of New Fairfield town center/business district, municipal town buildings and schools, and other properties within the proposed sewer service area as well as transporting the wastewater to the City of Danbury’s Wastewater Treatment Facility. The assessment included an estimate of projected flows for all properties within the planned service area and a comparison of total estimated flows to available capacity at the Danbury Wastewater Treatment facility. Design concept plans for the planned sewer service area included determination of collection system sewers and pump station locations. Part of the study included an evaluation of potential routes for transporting flows from the Fairfield Town Center service area to the City of Danbury collection system for treatment. 

sewer feasibility studyEstimated project budgetary costs for the sewer service area collection system, pump stations, and transport to the City of Danbury along with a phasing and implementation plan were included in the final draft report to the Town of New Fairfield. 

Throughout the course of the project, a number of meetings with the Town were held to obtain Town input and comments including one meeting at the completion of the initial assessment phase, one meeting at the completion of the concept design phase, and a series of meetings and presentations at Town Selectboard meetings to obtain public input during the roll out of the final report.

Tata & Howard provided preliminary and final design of 2.7 miles of gravity sewers, one main pump station, four remote, submersible pump stations, 2.3 miles of force mains, , and 4,000 linear feet of low pressure sewer. The project also includes identifying easements, land acquisition plans, preparation of permitting, and bidding assistance. 

Preliminary design included survey, soil borings, preparation of base mapping, identification of utility requirements, a radio path survey and an opinion of probable cost. 

sewer studyFinal design development includes final design of the main pump station, remote pump stations, gravity sewers, force main, and low-pressure sewers for connection to the City of Danbury collection system including site plans, profiles of force main and gravity sewers, pump station structures and chambers, electrical and controls, emergency generators, odor control, erosion and control plans, etc. Also includes design of the main pump station building designed to match the local aesthetic and mask it as a non-utility structure.

Construction Documents will be prepared by phasing construction under four contracts: 

  • Year 1 – Phase 1: Main Pump Station and force main for connection to the Danbury System and Collection System for the Town Center and commercial district (Sewer Sheds 2 [commercial],
    4, 5 and 8);
  • Year 2 – Phase 2: Collection System connecting schools, police, and fire facilities (Sewer Sheds 1 and 2 [residential]);  
  • Year 3 – Phase 3: Additional Collection System connecting additional commercial properties, The Birches 55+ community, The Woods at Dunham Pond 55+ community, The Good Shepherd Lutheran Church, and potential future land development along Route 37 (Sewer Sheds 3, 6, and 7).

Grafton Water District, Trinity Avenue Well Site and Pump Station

Tata & Howard provided engineering services for permitting, design, and bidding of the Trinity Avenue Pump Station at the Trinity Avenue Wellfield (new source) and provided 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), and 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 840 gallons per minute (gpm). The work under this contract included the completion of the Request for Site Exam and Pump Test Proposal for submission to MassDEP, installation and development of three (3) 18” x 12” gravel packed wells and pitless adapters, installation and development of approximately five 2-1/2” diameter observation wells, installation of two staff gages and piezometers, performing a five-day pump test, and collection and analysis of water quality.

The project also included an evaluation of alternatives for the access road including installation of a bridge or an open bottomed culvert, and Tata & Howard assisted with the preparation of permanent easements for the installation of utilities and roadway to the well site. In addition, Tata & Howard prepared and submitted an NOI to the Grafon Conservation Commission.

Design included double wythe block and interior concrete painted block with wood truss roof and asphaltic shingles. Security included chain link fence, gates, locks, intrusion alarms, and lighting. Tata & Howard 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 900 feet of new 12-inch water main for 4-log removal.

Tata & Howard also provided construction administration and resident observation services.

Steele Street Pump Station, New Britain, CT

Steele Street Pump Station

Tata & Howard provided engineering services for modifications to the Steele Street Pump Station including installation of a new constant-run type pump station with variable frequency drives; and design and installation of a new permanent outdoor diesel generator and automatic transfer switch.

In addition, T&H provided construction administration and resident observation services for the modifications to the pump station.

Steele Street Pump Station Standby Generator

Willis Road Wastewater Pumping Station, Gardner, MA

Tata & Howard was contracted to provide construction administration and part-time resident project representative services for the construction of upgrades to the Willis Road pump station.

The Willis Road Pump Station in Gardner, MA is a wastewater pumping station originally constructed in 1983. The pumping station was designed to handle a Total Maximum Daily Flow of 625 gallons per minute (gpm) or 900,000 gallons per day (gpd). The station pumps all the wastewater collected into the collection system through approximately 1,050 feet of 6-inch ductile iron force main.

The wastewater pumping station improvement project consisted of replacement of the station’s two 270 gpm centifugal pumps and motors, new control panels, new emergency generator, and upgrade of the existing pump building at a cost of $775,000.

 

 

 

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.

Trinity Avenue Pump Station, Grafton, MA

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.

 

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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.

Solar mixers for lagoons

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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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.

Water System Upgrades including Manganese Removal, Montgomery, VT

Tata & Howard designed and constructed the improvements to eliminate low and inadequate system pressures, construct a new source, pilot test filtration for manganese removal, design and construct required distribution system piping to connect the plant and storage tank with the system, design a new concrete storage tank, booster pump stations, and the filtration facility for manganese removal.  The  project was very successful and remains in great condition today.

Maine Water Company Pump Station

MaineWaterCo Barra Road PS building ext

Tata & Howard assisted Maine Water Company with mechanical, structural, and architectural design of a new high service zone booster pump station on Barra Road within the Biddeford-Saco water distribution system. The new pump station replaced the existing Alfred Road station, providing pumping capacity to meet current demands in a majority of the City of Biddeford as well as room for future expansion.  Funding for the project was provided in part by the Maine Drinking Water Program State Revolving Fund (DWSRF).

MaineWAterCo Barra Road PS interior

Mechanical design for the project consisted of sizing and selection of three (3) centrifugal booster pumps, associated piping, and appurtenances. The pumps were sized with input from a hydraulic model of the system developed by Tata & Howard, and they were selected to maximize the available flow from a 16” cast iron pipe line that crosses the Maine Turnpike from the water system’s major storage reservoir. A pipe gallery was incorporated into the slab and foundation design as well as insulated concrete form (ICF) foundation walls. Per the Owner’s request, the architectural design used colors and materials similar to the other buildings within the surrounding commercial office park. Also, a gable roof canopy was added to the design (pictured below) to help shield the emergency backup generator from the elements. Precautions were taken to ensure proper air flow and ventilation was achieved to meet the requirements of the generator.  Construction of the pump station was completed in 2015.

MaineWaterCo Barra Road PS overhang