Overview and Ecosystem Characteristics:
Most of this 16,024 acre (surface water not included) subbasin1
lies in the Massachusetts communities of Boylston and West Boylston
with parts extending into Sterling and Holden. Located in the Southern
New England Coastal Plains and Hills ecoregion2
of central Massachusetts, this area drains into the Wachusett Reservoir:
the largest body of open water in the greater Nashua River watershed.
The Southern New England Coastal Plains and Hills ecoregion is an
area with generally similar soils, vegetation, shape of the land,
and especially, moderate climate and bedrock geology (glacial tills
and outwash deposits). Topography is generally hilly, encompassing
numerous flatter wetlands, broad valleys, and floodplains.
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Land Ownership and
Patterns: The land-use pattern is nearly
75% forest (hardwood mixed with softwood) or wetland plus low-density
residential settlement as well as concentrated settlements and strip
development located near town centers and along major roads. Agriculture
(notably "hobby farms" and backyard horse paddocks), gravel
extraction, commercial operations, industry and other developed
land uses are less significant.
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Major Water Resource
Issues: Streamflow, as in most of New
England, has significant seasonal changes4.
Based on recent findings in an Hydrologic Analysis (inflow/outflow)
by Camp, Dresser, Mckee, under contract with EOEA for the Massachusetts
Watershed Initiative Nashua Team, the Wachusett sub-basin is currently
under a medium level of stress. With continued development and withdrawal
pressures, the sub-basin will continue as "medium stress"
by the year 2020. It should be noted that while there is a minimum
flow requirement for discharge over the Wachusett Dam, local and
regional water suppliers need to recognize the importance of continuing
demand for supply on the reservoir.
This means that the net 7Q10 outflow from the
sub-basin equals or exceeds the estimated natural 7Q10. 7Q10 is
the lowest consecutive 7 day streamflow that is likely to occur
in a ten year period in a particular river segment.
Because the Wachusett watershed is highly managed
for the Worcester and MWRA withdrawals, these withdrawals were not
considered in the evaluation of stress in the Wachusett Watershed-a
much more detailed analysis would be required to evaluate their
uses. Instead, the calculations were based on other uses of water
in the watershed, particularly withdrawals by Holden, Rutland, Princeton,
Sterling, and West Boylston. Based on these withdrawals, three of
the four subareas in the Wachusett Watershed were calculated to
have medium-stress in the future.
This subbasin features an extensive network
of streams and rivers feeding the reservoir including: Boylston,
Chaffin's (Unionville outlet), Gates, Malagasco, Malden, Scarlett
and Waushacum Brooks; though, all together these brooks make up
a comparatively minor percentage of the total inflow to the reservoir.
Though Wachusett Reservoir is principally fed
by the Stillwater and Quinapoxet Rivers-together both account for
about 30% of annual inflow5
-- these two are considered separate subbasins and are dealt with
separately in this Plan. The Wachusett Reservoir provides very high-quality
drinking water to a large portion of the Commonwealth's population
via the Massachusetts Water Resources Authority (MWRA) and Metropolitan
District Commission (MDC) Division of Watershed Management (DWM).
More than 90% of the water leaving the Reservoir is withdrawn by
the MWRA and only a small amount is released downstream to the South
The amount of permanently protected (owned by
MDC and others) undeveloped open space, 28.4% (surface water not
included), in the subbasin has meant that the water quality in the
reservoir remains excellent, indeed, to such an extent that filtration
treatment has to date been considered unnecessary. There are no
wastewater treatment plants or industrial discharges in this subbasin.
10.6% of total impervious surfaces6
--namely, paved areas such as streets, driveways, and parking lots
for this whole subbasin indicates that concerns of compromised
stormwater and other non-point sources7
of contaminants (for example: pesticides, fertilizers, oils, asphalt,
pet wastes, salt, sediment, human litter and other debris) is an
increasingly pressing concern. The majority of residents have on-site
septic systems although a number of homes will be serviced by the
new Holden-West Boylston Sewer Project.8
As for specific areas of concern, Wachusettt
Reservoir itself has non-native
mercury contamination (as found in fish tissue samples); thus, according
to the 1998 Nashua River Watershed Report Card, the Wachusett Reservoir
is rated as partially-supportive for biology and non-supportive
of fish tissue. However, its waters are crystalline with low turbidity,
bacterial counts, algal densities, and nutrients. On the other hand,
Gates Brook is considered to be the "most contaminated tributary"
in this subbasin with high nitrates and severe impairment for aquatic
life. West Boylston Brook is similarly impaired and has the highest
nitrate level. Both Gates and West Boylston Brooks are classified
by the MDC as "severely septic polluted", having the highest
fecal coliform loadings in this watershed, while Boylston and Malden
Brooks are considered "moderately septic polluted streams".
Scarlett Brook is considered to be severely
impaired for conductivity and fecal coliform which as with
the above mentioned streams is expected to rise due to high
numbers of improperly functioning septic systems and the area's
increasing density of development. Beaman Pond, Boylston, Chaffin's
(Unionville outlet), Malagasco, and Waushacum Brooks are other tributaries
in this subbasin which are severely impaired for conductivity or
Gates and Malagasco Brook, in particular, exhibit significant impacts
potentially caused by contamination (as yet to be identified). Not
withstanding these limitations, most of the small waterways in this
subbasin are healthy functioning ecosystems exceeding Class A standards
in many regards with low levels of phosphorus and other "non-point"
pollutants. Also, each of the above mentioned tributaries to the
Reservoir have low flows and, thus, contribute only a minor load
of "impaired" waters. There are no 303(d)-listed* impaired
water bodies in this subbasin.
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Priority Habitat Areas: The Reservoir
itself is important habitat for lake-nesting and lake-feeding birds.
The entire water surface with adjacent upland connects with the
Stillwater River as one large state-designated Natural Heritage
and Endangered Species Program Priority Habitat area.10
The BioMap Core Habitat area in this subbasin corresponds directly
with the NHESP Priority Habitat area, while BioMap Supporting Habitat
areas lie along the eastern edge of this subbasin.
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Goals and Recommended Actions
GOAL: Protect wildlife habitat
and migration corridors in the subbasin.
- Assist MDC, MassWildlife, other state agencies,
municipalities, and local land trusts in consensual transactions
to acquire additional open space in priority areas.
- Sponsor local events to raise public understanding
about native wildlife and the impacts of development patterns
on ecosystem and habitat integrity.
- Work with local conservation commissions to gain
their backing of natural resource/ habitat inventories.
- Continue MDC-DWM's Private Land Forestry program
which encourages private forest landowners to adopt forestry practices
- namely, forest management planning required by the Chapter 61
program that protect water quality
GOAL: Protect high-priority open space, vistas,
and community character in the subbasin.
- Encourage the use of MA Executive Order 418*
funding for "Open Space and Resource Protection Plans"
for each Massachusetts community in the Stillwater River subbasin.
- Conduct public education sessions to promote local
passage of Community Preservation Act*.
- Work toward ideal of at least 25-50% protected
open space in each municipality.
- Work with municipal officials to develop subdivision
standards that require proponents to devote at least 50% of land
(not including already undevelopable wet or steep land) for open
space conservation and encourage mixed-use development and cluster
zoning by-right bylaws.
GOAL: Increase recreational opportunities throughout
- Support the Wachusett Greenways group in its volunteer
efforts to link communities via multi-use intermunicipal trails
and open spaces, and in particular the Mass Central Rail Trail.
- Improve canoeing, fishing, and swimming opportunities
by removing weeds from water bodies.
- Educate the public and municipal departments (especially
Public Works Depts.) on efforts relating to invasive species*
identification and removal.
GOAL: Improve water quality in the basin.
- Conduct more detailed inflow/outflow studies given
stressed status of some waterways.
- Evaluate West Boylston and Holden's sewering project
for impact on surface water quality.
- Assist Boylston and West Boylston with its EPA's
Clean Water Act-mandated MS-4 Phase II stormwater requirements.*
These municipalities will be required to obtain permits to reduce
impacts to the receiving streams through the development of Best
(BMPs), elimination of cross-connections and significant public
education. CSO controls and the development of a long-range control
plan will be required.
- Identify the major sources of fecal coliform and
nitrate-nitrogen inputs to the river and work with communities
to address the problem.
- Identify the degree of threat from potential faulty/
illicitly discharging septic systems, which may result in bacterial
and nutrient contamination of nearby streams and groundwater.
- Identify underground storage tanks (USTs) and work
with communities to have them removed.
- Monitor effects of increasing urbanization to prevent
diminished groundwater recharge and to declining stream flow as
well as stream channel widening and downcutting.
- Help develop and disseminate Best Management Practices
for small-scale, hobby type agricultural operations.
GOAL: Reduce negative effects of development in
- Monitor uncontrolled runoff from construction sites
to prevent sedimentation of streams.
- Track increased imperviousness and both direct
and indirect riparian zone alterations that may increase stream
temperature and cause sedimentation.
- Help local volunteer board members responsible
for development and land-use rulemaking and enforcement get technical
assistance and information regarding fundamental and innovative
techniques to control and guide land use and development balanced
with adequate resource protection (e.g., Citizens Planner Training
Collaborative11 workshop offerings).
- Increase or establish staff hours of municipal
conservation agents to more effectively monitor runoff from construction
sites and assist with the preparation of relevant bylaws.
- Write and implement stormwater, erosion and