Water Quality in DCR Reservoirs 2008-2010
Intro
The 4,135-acre Wachusett Reservoir was built between 1897-1908 by damming the South Branch of the Nashua River. Wachusett Reservoir is the terminal supply reservoir of the of the MWRA system, feeding the new J.J. Carroll Water Treatment Plant. Together with the Quabbin Reservoir, they provide an clean source water to 47 communities, 2.2 million people and 5,500 industrial users in the metropolitan Boston area. The UMass project is aimed at providing assistance in several key areas to the Department of Conservation and Recreation (DCR), the body responsible for collection and safe storage of the source water, protection of reservoir water quality, and management of the watersheds.
Task 1 : Reservoir Modeling
Mathematical models can provide the ability to predict the response of DCR reservoirs to a variety of influences, allowing the models to be used as aids for operational decision making or for making long-term policy decisions. Factors that influence reservoirs include those, which may be outside of DCR control, such as loadings of water quality constituents, hazardous waste spills, and extreme weather events. Other factors such as water release and transfer policies, water quality control procedures, and watershed protection practices may be controllable by DCR or MWRA. Both reservoir water quantity and quality respond to these various influences. For models to be effective tools they must be proven to be reliable predictors of reservoir behavior when tested against a substantial body of data.
For this project, UMass is modeling processes at the Wachusett Reservoir using the two-dimensional CE-QUAL W2 model and the three-dimensional GEMSS model. This work will include developing and maintaining model-ready databases and calibrated models for Wachusett Reservoir. The FY09FY10 project has three specific reservoir modeling objectives:
- Continued water quality and hydrodynamic modeling using CE-QUAL W2, with a focus on modeling of contaminant spills into the western end of the reservoir.
- Continued development and application of the 3-dimensional GEMSS model, with a focus on model application to the north east end of the reservoir and the Cosgrove Intake area.
- Support of the MWRA financed Wachusett bathymetry and hydrodynamic data gathering project, especially the water velocity measuring efforts.
Task 2: Watershed Science and Management
Components of recent DCR/UMass research projects addressing the water supply reservoirs have included tasks that address watershed dynamics and management, including the nature and transport of water quality constituents such natural organic matter (NOM), nutrients (N, P), and microorganisms. 20 to 25% of the current project resources will be allocated to working with DCR to identify specific critical needs and determining the extent to which the UMass research team can provide solutions in support of those needs. Issues related to water quality, water quantity, climate change, emerging trace contaminants, and best management practices could be components of the work. Task 2 of this ISA includes meetings between UMass and DCR/MWRA staff to identify the critical needs, and initial work to address those needs. A January 2009 workshop and subsequent meetings are part of this effort. Modeling and assessing stormwater management issues in light of changing land use is likely to be a focus of this Task.
Principal Investigators
Research Assistants
- Bryan Sojkowski, Mikaela Laverty, Zhen Wang