EXECUTIVE SUMMARY

PURPOSE OF REPORT

The Bellingham Department of Public Works is interested in taking a measured, proactive approach to plan the future development of the Town of Bellingham water supply and distribution system. The purpose of this report is to update the previous water system master plan and to serve as a guide for future planning to provide a safe and reliable water supply throughout the Town of Bellingham.

This report will review the existing public water supply system, existing and future requirements, and the ability of the water system to expand in a cost effective manner. Supply alternatives will be evaluated and short-term and long-term supply development plans will be recommended. The report will examine the distribution system and how it can be developed while providing adequate flows and pressures, constructing new storage facilities, implementing new water supply sources and to provide a continuous supply of clean water.

The sections in this Executive Summary correspond to detailed sections in this report. The Executive Summary is a condensed version of the entire Water System Master Plan.

SUMMARY OF REPORT CONCLUSIONS

SECTION 1 - EXISTING SYSTEM

1.1_ The water supplies include 9 (nine) pumping stations rated for the corresponding pumping capacity in gallons per minute (gpm):

PS #1 360 g.p.m.

PS #2 225 g.p.m.

PS #3 475 g.p.m.

PS #4 450 g.p.m.

PS #5 200 g.p.m.

PS #7 295 g.p.m.

PS #8 470 g.p.m.

PS #11 250 g.p.m.

PS #12 350 g.p.m.

1.2_ All wells, except for PS #7 and #8, are treated with lime for corrosion control. In addition to lime, PS #7 and #8, are treated with alum, potassium permanganate, sodium hypochlorite, and greensand filtration.

1.3_ The distribution system consists of 89.4 miles of pipe. Depending on year of installation, the pipe materials are unlined or lined cast iron, asbestos-cement, steel, PVC, or cement-lined ductile iron. Currently the Department of Public Works specifies and installs C900 PVC pipe in roadways and Class 52 ductile iron concrete lined pipe in off road areas and easements.

1.4_ Storage facilities consist of the following three tanks, all with overflow elevations of 457 ft.

· Grove Street Standpipe - 3.1 million gallon standpipe at a ground elevation of 327 feet.

· Chestnut Street Standpipe - 1.5 million gallon elevated standpipe with a ground elevation of 347 feet.

· South Main Street Standpipe - 0.5 million gallon standpipe at a ground elevation of 357 feet.

SECTION 2 - WATER SUPPLY REQUIREMENTS

2.1 Average day demand has fluctuated from 1.66 Million Gallons per Day (MGD) in 1992 to 1.37 MGD in 2000. Maximum day demand has fluctuated from 2.89 MGD in 1992 to 2.09 MGD in 2000.

2.2 Unaccounted for water, as presented in the Annual Statistical Reports, has ranged from a high of 45% in 1994 down to a low of 20% in 2000.

2.3 Per-service consumption has ranged from 403 gallons per service per day (gpsd) to 274 gpsd between 1992 and 2000. Over the past five years the per-service consumption has averaged 281 gpsd.

2.4 Total number of services has fluctuated from 4,878 in 1992 to 4,978 in 2000 due to recently improved accounting practices.

2.5 Average day demand is projected to be 2.16 MGD in 2005, increasing to 2.54 MGD in 2010.

2.6 Maximum day demand is approximately 2.0 times the average day demand, and is estimated to be 4.32 MGD in 2005, increasing to 5.07 MGD in 2010.

SECTION 3 - ADEQUACY OF SUPPLY FACILITIES

3.1 The wells have a reported combined Safe Yield of 3,075 g.p.m. (4.42 MGD).

3.2 With all wells in service, the wells can provide maximum day demand through the year 2009.

3.3 With the largest supply out of service (PS #7 & #8/treatment plant), the remaining wells will not be able to provide maximum day demands by 2003.

3.4 Bellingham is not currently developing any new sources. However, PS #13 and #10, are two possible new sources. PS #13 is expected to provide 350 g.p.m. The capacity of PS #10 is expected to be 250 gpm, based on a preliminary test conducted in 1971.

3.5 The water supplies currently are in compliance with all primary drinking water standards as established by the EPA and the Massachusetts Department of Environmental Protection. Secondary standards for iron and/or manganese are currently exceeded at all other wells, except for PS #12 and the PS #7 & #8 water treatment plant.

3.7 There is not sufficient auxiliary power at the pumping stations to meet projected maximum day demand through 2010. Installation of, or provisions for, auxiliary power shall be required by 2004.

SECTION 4 - ADEQUACY OF EXISTING DISTRIBUTION SYSTEM

4.1 Hydraulic analysis of the water distribution system has identified problems within the distribution system. These problems include low pressures in high elevation areas and lack of available flow in dead-end water mains.

4.2 The existing water distribution system was evaluated by a number of criteria. These criteria included system pressures, pipe velocities, head losses, available fire flows, and age of piping.

4.3 Fire hydrant flow tests were conducted at nineteen (19) locations throughout Bellingham by ISO Commercial Risk Services, Inc. in May 1998. These tests indicated that at 10 of the 19 test sites, the system could not deliver the required fire flow.

4.4 The water distribution system was evaluated by the use of a computer model. The model used for the hydraulic analysis in this report was Cybernet Version 3.1 by Haestad Methods, Inc.

4.5 The Bellingham water distribution serves elevation limits ranging from 187 feet to 361 feet.

4.6 The water distribution system model was calibrated by performing flow tests at 17 locations throughout the Town of Bellingham, and adjusting hydraulic factors such as C-values and pipe status until the model output flows were within 10 percent of the actual flow test values.

4.7 Hydraulic analysis of the distribution was completed under Average Day, Maximum Day, and Peak Hour Demands. The model was simulated based on operational conditions of the distribution system during the flow testing on October 24, 2000. Other sets of operational conditions were also investigated in the hydraulic analysis, including, but not limited to varied well and tank operational settings.

4.8 Under most demand conditions, all distribution system criteria are met, with the exception of fire flows. Residential fire flows are not available at all locations within the distribution system, and under Peak Hour Demands, low pressures are seen under fire flow conditions as well.

4.9 Distribution storage facilities serve several functions within a distribution system. The primary function is to provide storage for fluctuations in the daily usage of water.

4.10 Proposed improvements to the water system were discussed and analyzed. It was determined that if all the recommended improvements are implemented, the distribution system will be able to meet all hydraulic requirements in the areas of flow, head loss, pressure, and pipe velocity.

RECOMMENDATIONS

SECTION 5 - SUPPLY IMPROVEMENTS

5.1 Water supply improvements are recommended to increase supply capacity as required to improve reliability and meet future demands.

5.2 The water department should pursue testing and development of the future well sites - PS #13 and PS #10.

5.3 The Bellingham DPW should install auxiliary power facilities at PS #3, #4 & #11, PS #1 & #2, and PS #12.

5.4 The Bellingham DPW should consider the installation of auxiliary power facilities at all future supply sites.

SECTION 6 - DISTRIBUTION SYSTEM IMPROVEMENTS

6.1 Distribution system improvements are recommended to:

· Improve fire flows

· Replace undersized water mains

· Replace aging unlined cast iron mains

· Decrease the number of dead ends

6.2 In developing alternatives to eliminate deficiencies within the existing distribution system, the future expansion and service requirements of the distribution system must be considered.

6.3 In order to improve flow and pressure deficiencies within the system, there are several pipe installations and improvement projects which need to be performed. Table 7-1 lists twenty improvement projects with associated costs and the three with the highest priority are listed as follows:

· Replace the 6-inch water mains in Blackstone Street with 8-inch water mains in the South Main Street area.

· Install 3,200 linear feet of 12-inch water main in Mechanic Street from South Main Street to Maple Street

· Replace the old 10-inch cast iron water main in Center Street with 10,500 linear feet of new 12-inch water main.

6.4 The existing water storage facilities were found to be in good overall shape. The only tank which requires some maintenance is the Chestnut Street Tank. Maintenance to be performed includes repairs to pitted interior tank areas and repainting of the exterior of the tank.

6.5 Once improved, the water distribution system will meet virtually all the hydraulic requirements for a distribution system in its current configuration, thus two separate zones of high and low pressure are not deemed necessary at this time.

6.6 A complete SCADA system for centralized monitoring and control of the system’s pump stations, treatment processes, and storage facilities is recommended for installation.

SECTION 7 - MASTER PLAN IMPLEMENTATION

7.1 Regular water system operations and maintenance activities including water main flushing and gate valve exercising are very effective in maintaining the full capacity of the existing facilities.

7.2 Financing of system improvements can be achieved using water rate increases, grants/loans, system development charges, and betterments.

7.3 A Capital Outlay Budget has been prepared recommending spending between $582,000 and $1,342,000 annually over the next ten years.