Massachusetts Water Resources Authority
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The Massachusetts Water Resources Authority (MWRA) is a public authority in the Commonwealth of Massachusetts that provides wholesale drinking water and sewage services to certain municipalities and industrial users in the state, primarily in the Boston area.
The authority receives water from the Quabbin and Wachusett Reservoirs and the Ware River in central and western Massachusetts. It also operates an effluent tunnel in Boston Harbor for treated sewage as well as a treatment center on Deer Island at the mouth of the harbor, among other properties.
The MWRA was created in 1986 and assumed sewage and wastewater treatment functions from the former MDC (Metropolitan District Commission), now the DCR (Department of Conservation and Recreation), which still maintains the watershed lands.
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[edit] MWRA water system overview
The Massachusetts Water Resources Authority and the Massachusetts Department of Conservation and Recreation (DCR) own and operate the collection, treatment, distribution, and storage facilities that supply drinking water to some forty municipalities in the metropolitan Boston area. This water system design was based upon the purchase and subsequent protection of an entire watershed. This design assures that the water remains as pristine as possible. However, modern regulations require that all supplies of drinking water be chemically treated regardless of the source.[1] Additions to the MWRA water system throughout its history have resulted in redundancies that allow major sections of the water system to be shut down for repair or maintenance.
[edit] Water flow
Water flows from the MWRA's main storage facility, the Quabbin Reservoir in central Massachusetts, through the Quabbin Aqueduct to the Wachusett Reservoir in and around Boylston and Clinton.[2] Tributary rivers and streams comprising the Wachusett watershed, a 108 square mile (280 square kilometer) drainage basin, also feed the Wachusett Reservoir. At the eastern end of the Wachusett Reservoir, water enters the Cosgrove Tunnel at the Cosgrove Intake. The Cosgrove Tunnel feeds both the MetroWest Water Supply Tunnel (MWWST) and the Hultman Aqueduct. The MWWST starts from the Carroll Water Treatment Plant in Marlborough. The Hultman branches off at Framingham in two directions. The smaller branch, the Weston Aqueduct, empties into the Weston Reservoir in Weston. The main branch continues to the Norumbega Reservoir, also located in Weston.[2]
[edit] Redundancy
In an emergency, water can be treated with sodium hypochlorite at any point in the system by deploying Mobile Disinfection Units (These are trailer-mounted units that the MWRA has stored at strategic locations throughout its system). Since completion of the covered storage reservoirs in Ludlow, Weston and Stoneham, all of the open distribution reservoirs (Spot Pond, High Fells, Chestnut Hill, Waban, Norumbega and Weston) and backup storage reservoirs (Sudbury and the three reservoirs of the Framingham system) and the Sudbury and Wachusett Aqueducts consititute a backup network for emergency use. An additional covered storage reservoir is currently under construction at th Blue Hills in Quincy.
[edit] John J. Carroll water treatment plant
Located at the town lines of Marlborough, Northborough, and Southborough, Massachusetts, this facility replaces the one used previously only for pH control.[3] It comprises four ozone generators with diffusers and five concrete contact chambers with a volume of 11.3 million gallons (42.7 million liters). The plant has a capacity of 275 million gallons (1.04 billion liters) per day, on an average day or 405 million gallons (1.53 billion liters) per day, at peak level. It cost US$340 million.[3]
After being treated at the Carroll Treatment Plant, water goes through the Metro West Water Supply Tunnel to covered storage tanks in Weston and Stoneham. An additional tank is scheduled for construction at the Blue Hills in Quincy and there are two tanks in Ludlow that feeds the communities of Chicopee, Wilbraham and South Hadley (Fire District No. 2).
[edit] Electrical generation
The system includes three hydropower stations, with a total capacity of 8 MW.[4] Water released to the Swift River flows through the turbines at Winsor Station below the Winsor Dam. Water transferred from Quabbin to Wachusett can pass either through the turbines at Oakdale or through bypass pipes when flow requirements exceed turbine ratings. Water released from Wachusett into the Cosgrove Tunnel passes through the Cosgrove turbines.(There are 4 turbines in the Wachusett Gatehouse, located at the start of the Wachusett Aqueduct, and one at the head of the Weston Aqueduct in Southborough, but those in Clinton have not been used in over 40 years. The turbine at Southborough has also been inactive for a long period.)[2][3]
MWRA power generation
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The Quabbin Aqueduct connects the two reservoirs, and relies upon gravity to accommodate the three separate operational needs. First, diversion of water from the Ware River into the Quabbin Reservoir uses this aqueduct. Second, water transfer from the Quabbin Reservoir to the Wachusett Reservoir, through a hydropower station or a bypass pipe, uses it as well. The bypass valves are non-regulating valves, and when opened, only the head in the Quabbin Reservoir and the physical characteristics of the aqueduct govern the flow. Because the turbines are flow limited, the bypass mechanism permits transfer rates nearly twice as high as are possible through the turbines. Operationally, the single aqueduct fulfills three purposes, but only one operational mode is possible at a given time.[5]
[edit] Service Area
MWRA Service Area -- the area consisting of the following political subdivisions: Arlington, Ashland, Bedford, Belmont, Boston, Braintree, Brookline, Burlington, Cambridge, Canton, Chelsea, Dedham, Everett, Framingham, the north sewer district of Hingham, Holbrook, Lexington, Malden, Medford, Melrose, Milton, Natick, Needham, Newton, Norwood, Quincy, Randolph, Reading, Revere, Somerville, Stoneham, Stoughton, Wakefield, Walpole, Waltham, Watertown, Wellesley, Westwood, Weymouth, Wilmington, Winchester, Winthrop, and Woburn.
[edit] Total Water Demand and Wastewater Generation
MWRA Total Water Demand and Wastewater Generation [1]
| Calendar Year |
Water Demand |
Wholesale Water |
Total Wastewater Generation |
Dry Day Wastewater |
|---|---|---|---|---|
| 1996 | 256 mgd | 222 mgd | 426 mgd | N/A |
| 1997 | 258 mgd | 226 mgd | 353 mgd | N/A |
| 1998 | 260 mgd | 231 mgd | 412 mgd | N/A |
| 1999 | 276 mgd * | 245 mgd* | 344 mgd | 307 mgd |
| 2000 | 252 mgd * | 229 mgd* | 362 mgd | 331 mgd |
| 2001 | 247 mgd * | 229 mgd* | 346 mgd | 305 mgd |
| 2002 | 237 mgd | 219 mgd | 340 mgd | 309 mgd |
| 2003 | 222 mgd** | 214 mgd | 382 mgd | 333 mgd |
| 2004 | 216 mgd** | 208 mgd | 356 mgd | 327 mgd |
| 2005 | 225 mgd** | 213 mgd | 403 mgd | 342 mgd |
| 2006 | 212 mgd | 201 mgd | 380 mgd | 322 mgd |
- * Total withdrawals and water sales included an additional (temporary) demand from Cambridge while it rebuilt its own water treatment plant. For calendar year 1999, 15 mgd; calendar year 2000, 14 mgd; and calendar year 2001, 6 mgd.
- ** Total withdrawals do not include an additional demand associated with Carroll Water Treatment Plant start up and testing activities. For calendar year 2003, 2,710 MG (annual average 7.4 mgd); calendar year 2004, 1,326 MG (annual average 3.6 mgd); calendar year 2005, 12,264 MG (annual average 33.6 mgd).
[edit] Rates
Final FY08 Water and Sewer Assessments [2] [3] [4]
| Proposed FY08
Final |
FY07 Final | $ Change from
FY07 |
% Change from
FY07 |
|
|---|---|---|---|---|
| Water | $168,292,702 | $163,124,954 | $ 5,167,748 | 3.2% |
| Sewer | 349,505,130 | 332,233,810 | 17,271,320 | 5.2% |
| Total | $517,797,832 | $495,358,764 | $22,439,068 | 4.5% |
Annual Water and Sewer Retail Rate Survey - November 2007
"The MWRA Advisory Board... was established by the state Legislature to represent the 60 communities in the MWRA service area. Through annual comments and recommendations on the Authority’s proposed capital and current expense budgets and rates, the Advisory Board provides a ratepayer perspective on the MWRA’s plans and policies to improve the region’s water and sewer systems."
"The water and sewer rates cited on the following pages for average annual household use are based on the industry standard of 120 hundred cubic feet (HCF), or approximately 90,000 gallons. Actual usage per household will vary. The principal goal of the survey is to track retail rate increases from year to year using a consistent standard."
Combined Annual Water & Sewer Charges in MWRA Communities
- 1991 - 2007:
- $443 $523 $559 $570 $593 $626 $648 $674 $699 $724 $751 $794 $842 $889 $946 $1,006 $1,069
MWRA SYSTEMWIDE SUMMARY DATA 2007
- Avg. combined water and sewer cost $1,068.54
- Percent change from prior year 6.2%
WATER BILLING FREQUENCY
- Semi-Annual 16
- Tri-Annual 2
- Quarterly 38
- Monthly 4
WATER RATE STRUCTURE
- Ascending Block with Base Charge 22
- Ascending Block only 15
- Flat Rate with Base Charge 7
- Flat Rate only 15
- Fixed Fee 1
[edit] Combined annual water and sewer charges in MWRA municipatilites
(Charges include MWRA, community and alternatively supplied services; Rates based on average annual household use of 120 hundred cubic feet (HCF), or approximately 90,000 gallons)
2007 Water & Sewer Retail Rate Survey - MWRA Advisory Board November 2007
| Water | Sewer | Combined | Change | |
|---|---|---|---|---|
| Belmont (W/S) | 590.20 | 1,011.76 | 1,601.96 | 4.5% |
| Boston (W/S) | 421.96 | 542.73 | 964.68 | 9.5% |
| Brookline (W/S) | 540.00 | 690.00 | 1,230.00 | 2.0% |
| Cambridge (S/partial W) | 340.80 | 772.80 | 1,113.60 | 0.0% |
| Framingham (W/S) | 397.56 | 408.96 | 806.52 | -7.2% |
| Lexington (W/S) | 379.20 | 873.60 | 1,252.80 | 0.0% |
| Milton (W/S) | 541.20 | 951.36 | 1,492.56 | 1.2% |
| Newton (W/S) | 467.20 | 725.60 | 1,192.80 | 5.8% |
| Quincy (W/S) | 415.20 | 723.24 | 1,138.44 | 7.3% |
| Somerville (W/S) | 432.03 | 761.88 | 1,193.91 | 7.4% |
| Waltham (W/S) | 324.48 | 578.76 | 903.24 | 16.9% |
| Watertown (W/S) | 401.18 | 782.40 | 1,183.58 | 9.2% |
| Winthrop (W/S) | 500.40 | 806.40 | 1,306.80 | 11.0% |
| AVERAGE | $421.19 | $647.35 | $1,068.54 | 6.2% |
[edit] MWRA debt
"The biggest driver of MWRA's budget is debt service on the bonds that financed major capital improvement projects.
Since its creation in 1985, MWRA has completed $6.8 billion worth of upgrades to its water and sewer systems. These projects have all but reversed the effects of neglect and underfunding of the previous decades.
With the sewer treatment facilities on Deer Island complete, the clean-up of Boston Harbor has gained national acclaim as one of the greatest environmental success stories of our time. On the drinking water side, massive upgrades to water infrastructure, including a state-of-the-art ozone disinfection plant and covered storage tanks throughout the district guarantee some of the best drinking water in the country for generations to come. But these improvements have come at a price."What Drives MWRA's Rates
[edit] 2006 System expansion
Due to the large fixed costs, in 2006 proposals were considered to expand access to the system, to spread out the expense.[5] [6] [7] As the dominant water use institution in the state, any system policy changes are controversial, dating back to the creation of the Quabbin Reservoir and the usage of water from the rural western part of the state by the eastern urban Boston metropolitan area.
[edit] Annual test reports
Water test results must be made public annually. The MWRA's Drinking Water Test Results for 2005 were Published June, 2006. [8]
Previous years, 1998-2005: http://www.mwra.state.ma.us/water/html/awqr.htm
[edit] Fluoridation
The MWRA has fluoridated its drinking water since the 1980s, maintaining a target fluoride level of 1.0 parts per million.[6]
[edit] See also
[edit] References
- ^ Safe Drinking Water Act. Retrieved on 2006-12-01.
- ^ a b c MWRA water system. Retrieved on 2006-12-01.
- ^ a b c John J. Carroll water treatment plant. Retrieved on 2006-12-01.
- ^ Electrical power generating plants. Retrieved on 2006-12-07.
- ^ Water system configuration. Retrieved on 2006-12-01.
- ^ MWRA - Media Advisory, Fluoride
