RIVERBRIDGE VILLAGE - 65 River Road West, Berlin, Massachusetts
Provencher Engineering was contracted by the site’s civil engineer / site designer, Waterman Design Associates, Inc. of Westborough, Massachusetts to coordinate, design, and secure permits for two new public water supplies and a wastewater treatment and disposal system for a proposed 66,000 gallons per day mixed-use commercial, residential, retail, and senior care planned community. Master planning of both public water supplies and a wastewater treatment and disposal facility was initially conducted.
Next, the design and permitting of a Phase 1 water supply pump station was conducted. This Phase 1 system was located at an adjacent property known as River Run, which is an approved undeveloped residential condominium community that already had two approved public water supply wells. This Phase 1 pump station was designed, approved, and constructed, and currently provides 5,000 gallons of temporary potable water for Phase 1of Riverbridge. This Phase 1 system allowed for immediate construction of a gas station and daycare facility, without the need to build the larger 66,000 GPD system initially, saving significant initial capital expenditures.
Once the Phase 1 pump station design was complete, we immediately commenced engineering on the full-build 66,000 GPD water & wastewater systems. We secured a DEP permit for the siting of 4 new bedrock public water supply wells. We coordinated and directed the well drilling, pump testing, and field monitoring to determine if there was potential for impacts to streams and wetlands from pumping the wells, and to determine if there was potential impacts to the wells from the surrounding environment.
To reduce the potential for draw down impacts to the environment from the wells, and from the envronmental contamination to the wells, we took special measures when drilling the 4 bedrock wells, including installing roughly 60 feet deep of extra well casing into the bedrock, so that drawdown impacts to the surficial (water table), and the potential to draw surface water into the wells would be minimized.
Two 1.5-inch steel hand-augered well point piezometers, with 1-foot long stainless steel well screens, were installed, one in a wetland, and the other beneath a stream bed using a PVC casing. A drilled monitoring well in the proposed leach field was also monitored. In total, we installed 8 transducers (water level recorders) in the four bedrock source wells, in the wetland and stream pizometers, in the leach field monitoring well, and one at the stream bottom used as a staff gauge.
The water levels were monitored for over a month, including 2 weeks before the pump tests to establish a baseline, then during 4 individual 1-day step tests at each well, during the 5-day simultaneous pump test on the 4 bedrock wells, and then for one week following pumping. The intent was to determine if pumping produces any drawdowns at the observation points, compared to the baseline data; and if any drawdowns return to baseline conditions after pumping ends. Comparing stream stage to the "water table" under the stream, and monitoring the wetlands and leach field determines if surface water or wastewater might be drawn into the pumping bedrock wells.
A Source Final Report on the wells, pump tests, and field monitoring was submitted to DEP with our design of the entire water supply system, including a pumping station, 132,000 gallon bolted steel water storage tank, and seperate fire protection and potable distribution systems. A New Source Approval for the construction of the 66,000 GPD full-build water supply was granted in 2011.
Construction of the full-build water supply system, including a 100,000 gallon above ground steel storage tank and 24'x24' above ground pump station building commenced in 2016 and was completed in 2018. The new water supply infrastructure was activated in early 2018 and presently served water to the mixed use development. The remaining phases of the development are under way, including a restaurant, hotel, and condominiums. The smaller Phase 1 pump station has been disconnected from Riverbridge, and will become the permanent public water supply for the 10,000 GPD River Run residential development, which is completely seperate from Riverbridge. The River Run pump station was designed to be expandable so that booster pumps and an exterior atmospheric storage tank can be added for the future River Run. A storage tank and booster pumps were not needed for the Phase 1 Riverbridge system because the Phase 1 demand was small compared to the future River Run demands.
Careful master planning and design of these two water systems was critical to meet Riverbridge's construction schedule and budget, by designing the systems so that capital was only spent as needed based on project phasing, and designing the systems to be expandable to accommodate future phases.
