Water Quality


The goal of this page is to show a snapshot of water quality across Hanover over time so consumers can make informed choices as to how they utilize their water.  Below the table are links to more detailed water quality results.

The table below is a summary of data from the DPW's general water quality program.  The zones listed in the table are geographic areas in Town.  Samples are taken weekly from various town-owned sites.   We also invite volunteers to be part of the regular testing program.   Our goal is to have a broad representation of data from across the entire community.  Treatment plant finished water is tested at least once a day. 

Below the table are links to maps showing the area of each zone.

Location When Samples Tested Avg Iron Iron
Rating
Average
Manganese
Manganese
Rating
Average
Color
Color
Rating
Zone 1A August 2015 4 0.018 0.028 4.8
September 2015 1 0.060 0.030 6.0
October 2015 4 0.018 0.023 3.2
November 2015 3 0.100 0.050 8.3
December 2015 3 0.040 0.056 1.5
January 2016 3 0.025 0.036 3.5
February 2016 4 0.030 0.036 5.0
March 2016 4 0.060 0.028 0.5
April 2016 2 0.015 0.028 4.0
May 2016 1 0.000 0.000 0.0
Zone 1B August 2015 7 0.011 0.018 5.0
September 2015 6 0.012 0.021 3.3
October 2015 7 0.010 0.023 5.3
November 2015 10 0.013 0.024 2.8
December 2015 9 0.010 0.021 3.0
January 2016 9 0.010 0.017 2.8
February 2016 12 0.018 0.018 4.8
March 2016 9 0.027 0.023 0.7
April 2016 4 0.010 0.017 1.0
May 2016 2 0.000 0.000 0.0
Zone 2 August 2015 30 0.020 0.072 15.8
September 2015 26 0.024 0.057 9.5
October 2015 25 0.029 0.029 6.1
November 2015 33 0.031 0.015 3.3
December 2015 30 0.029 0.014 2.4
January 2016 30 0.028 0.013 1.8
February 2016 40 0.036 0.012 4.2
March 2016 40 0.026 0.013 1.8
April 2016 20 0.025 0.016 2.1
May 2016 10 0.018 0.013 1.8
Zone 3 August 2015 12 0.024 0.013 3.9
September 2015 15 0.030 0.017 4.4
October 2015 18 0.056 0.016 6.4
November 2015 26 0.062 0.017 2.0
December 2015 24 0.052 0.015 3.2
January 2016 24 0.056 0.013 3.8
February 2016 32 0.044 0.015 4.2
March 2016 32 0.044 0.014 3.0
April 2016 16 0.031 0.015 3.7
May 2016 8 0.020 0.019 2.0
Zone 4A August 2015 26 0.019 0.029 3.9
September 2015 19 0.043 0.035 7.9
October 2015 28 0.029 0.024 3.4
November 2015 27 0.035 0.020 3.0
December 2015 24 0.034 0.022 3.6
January 2016 24 0.032 0.018 3.8
February 2016 32 0.036 0.020 3.9
March 2016 32 0.030 0.018 2.0
April 2016 16 0.020 0.021 3.9
May 2016 8 0.015 0.018 2.5
Zone 4B August 2015 7 0.011 0.020 5.1
September 2015 6 0.012 0.020 3.7
October 2015 8 0.015 0.024 2.5
November 2015 9 0.022 0.017 5.2
December 2015 9 0.015 0.016 1.5
January 2016 9 0.013 0.019 2.7
February 2016 12 0.016 0.020 2.8
March 2016 12 0.021 0.023 2.6
April 2016 6 0.013 0.024 2.5
May 2016 3 0.010 0.015 3.0
Pond Street WTP August 2015 62 0.010 0.041 3.3
September 2015 59 0.013 0.037 2.0
October 2015 61 0.010 0.038 2.7
November 2015 58 0.012 0.048 2.3
December 2015 58 0.012 0.032 1.6
January 2016 61 0.013 0.032 1.3
February 2016 57 0.013 0.032 0.9
March 2016 60 0.011 0.034 1.1
April 2016 75 0.013 0.039 1.1
May 2016 81 0.013 0.036 1.1
Beal WTP August 2015 32 0.021 0.013 0.2
September 2015 30 0.017 0.014 0.0
October 2015 32 0.022 0.015 0.2
November 2015 30 0.030 0.014 0.0
December 2015 31 0.042 0.022 0.2
January 2016 39 0.024 0.011 0.1
February 2016 47 0.021 0.012 0.3
March 2016 42 0.024 0.015 0.1
April 2016 54 0.017 0.015 0.3
May 2016 65 0.014 0.011 0.4
Broadway WTP August 2015 32 0.012 0.025 0.7
September 2015 30 0.019 0.029 0.5
October 2015 31 0.017 0.022 0.3
November 2015 30 0.016 0.014 0.1
December 2015 31 0.023 0.015 1.1
January 2016 43 0.022 0.012 2.0
February 2016 46 0.028 0.011 1.0
March 2016 42 0.030 0.012 1.0
April 2016 55 0.022 0.011 0.6
May 2016 67 0.022 0.012 0.6


The color scheme in the ratings are: green is good, yellow is fair, and red is poor.

Iron (mg/l): 0-0.15 Green (good). 0.16-0.3 Yellow (fair), >0.3 Red (poor)
Manganese (mg/l): 0-0.035 Green (good). 0.036-0.05 Yellow (fair), >0.05 Red (poor)
Color (standard color units): 0-8 Green (good). 8.01-15 Yellow (fair), >15 Red (poor)


ssClick on the links below for maps of the sample zones

                             Sample Zone 1A
                             Sample Zone 1B
                             Sample Zone 2
                             Sample Zone 3
                             Sample Zone 4A
                             Sample Zone 4B




(Under Construction: Description of iron, manganese and color..............)

(Under Construction: Links to overall test result spreadsheets..............)

                    Click here for listing of General Water Quality Data (PDF)


Disinfection Byproducts

The Town is currently working to reduce disinfection byproducts which form when chlorine in the water reacts over time with residual organic material that is also in the water.  We are currently in violation of Federal standards for total trihalomethanes (TTHM's) at one site in North Hanover.    Please click on the following link for more information about disinfection byproducts and what we are doing to try to reduce them in the town's water system.  Click here for the Disinfection Byproduct Page




Water Treatment Plants

The Pond Street Water Treatment plant is a conventional treatment plant designed to remove iron, manganese, organic color, and turbidity from the raw water.   The raw water quality varies depending on the combination of wells that are being used.  Readers of this page will see that the plant effectively and consistently removes iron and color.   Manganese is more challenging due to tight tolerances in water chemistry that are often in conflict with the color removal process.   The average raw water quality at Pond Street in 2014 has been 0.57 mg/l of manganese, 82 units of color, and 1.06 mg/l of iron.  The average finished water quality for the same period has been 0.055 mg/l of manganese, 1 unit of color, and 0.026 mg/l of iron.  Our treatment goals are less than 0.15 mg/l of iron, less than 8 parts of color, and less that 0.05 mg/l of manganese.

The Beal Water Treatment plant is a manganese-greensand treatment plant designed to remove iron, manganese,  and turbidity from the raw water.   The raw water quality tends to be quite consistent from day to day. Readers of this page will see that the plant effectively and consistently removes iron, manganese, and color.    The average raw water quality at Beal in 2014 has been 0.56 mg/l of manganese, 30 units of color, and 2.64 mg/l of iron.  The average finished water quality for the same period has been 0.02 mg/l of manganese, 0 units of color, and 0.04 mg/l of iron.  Our treatment goals are less than 0.15 mg/l of iron, less than 8 parts of color, and less that 0.05 mg/l of manganese.

The Broadway Water Treatment plant is a manganese-greensand treatment plant designed to remove iron, manganese,  color and turbidity from the raw water.   The raw water quality tends to be quite consistent from day to day. Readers of this page will see that the plant effectively and consistently removes iron, manganese, and color.    The average raw water quality at Broadway in 2014 has been 0.39 mg/l of manganese, 71 units of color, and 0.71 mg/l of iron.  The average finished water quality for the same period has been 0.02 mg/l of manganese, 0 units of color, and 0.02 mg/l of iron.  Our treatment goals are less than 0.15 mg/l of iron, less than 8 parts of color, and less that 0.05 mg/l of manganese.

(Under Construction: Links to water treatment result histories in PDF format)

Raw and finished water quality data is also available for each of the Town's water treatment plants from our Open Data page.

                    Click here to go to the DPW's Open Data Page


Water Consumer Confidence Reports

The DPW is proactive in its quest to provide the highest quality of water possible. Please click on the following link for a narrative of the steps and tests that are performed to ensure the quality of the water over the past few years: 

2016 Consumer Confidence Report

2015 Consumer Confidence Report

2014 Consumer Confidence Report

2013 Consumer Confidence Report

2012 Consumer Confidence Report

2011 Consumer Confidence Report

2010 Consumer Confidence Report