We receive calls about higher than normal water bills on a regular basis. Under normal circumstances we’d schedule an appointment to visually check the meter, look for leaks, etc. However, we are not entering homes or businesses for the foreseeable future unless it’s for an emergency.

When confronted with a high bill, customers often ask questions such as where did the water go or how could I possibly use that much water. Well the simplest answer is that from the limited information available, there is really no possible way for us to know where the water went once it went through the meter. The information used to generate the bill – start and end meter readings can be augmented with one or two readings taken during the billing cycle and that is about it. A similar question would be where did I drive my car over the past 3 months based on start/end odometer readings. The result would be a similar answer - we don’t know where you went, just how far.

However, if monthly readings are available then the pattern and volume of use may make one explanation more reasonable than others but in the end it’s our best guess. In some cases, an explanation can’t be found and it comes down to meter accuracy – did the water go through the meter or not. Meters are typically pulled and sent to a vendor for testing when this occurs. 

 Once the readings are verified then we can start asking questions such as:



Is the issue the dollar amount, the volume of use or both?

Water rates have increased by quite a bit over the past several years due to capital investments in the system including the water treatment plant and the replacement of several miles of water mains. The annual rate increase ranged from 15-24% per year depending on the year. This makes comparing bill amounts from year to year somewhat difficult. We recommend looking at the volume used from quarter to quarter or year to year as the best indication of a change in water use.


Is there a leak?

This is the most common issue we find and the culprit is usually a toilet. Designed to efficiently dispose of water, toilets are one of the few places in a home where water can disappear without a trace – no puddle, ceiling stain or drip. These leaks are often quite small but are continuous – every minute of every day. An eighth of a gallon per minute leak consumes 180 gallons per day, 5,400 gallons per month and 16,200 gallons per quarter. The higher volume of use leads to a higher cost per gallon because of the increasing block rate structure.

The easiest way to check for a leak is to read the meter before you go to bed and again when you wake up. If you didn’t use any water overnight but the meter registered use then there is leak. If you record the times of the meter readings then you can calculate the flow.

Checking toilets is easy, especially if you have some food coloring. Start by removing the lid on the tank. Inside the tank there is an overflow drain that is typically a tube extending up from the bottom of the tank or it could be cast into the side of the tank. The drain is to prevent the tank from overflowing in the event the float valve assembly fails to properly regulate the water level and it dumps the water to your septic system. The water level in the tank should be at least a quarter of an inch lower than the drain rim.

At the base of the tank is the flapper valve that opens when the toilet is flushed. The valve might not seat properly and water can leak into the bowl. Sometimes you can see water running down the side of the bowl or some turbulence in the bowl but these leaks are often small and hard see. Add some food coloring to the water in the tank until it has a distinct color. Wait and see if the water in the bowl changes color as well. If you haven’t flushed the toilet and the water in the bowl changes color then the flapper valve is leaking. Hundreds of dollars in water bills can be saved by installing $50 or less in parts.


Was the irrigation system used?

Irrigation systems can use a tremendous amount of water, sometimes several thousand gallons per day depending on the system’s size and how the automatic timer is configured. We recommend setting the timer yourself or at the very least discuss the timer settings with the person that does set it up. The installer should be able give you an estimate of how much water the system will use and you can always measure it using the water meter. We suggest using the rate from the highest tier when calculating the operational cost of the system.


Was your bill recently estimated?

If you’ve received a notice from us saying that we need to access the meter to repair the radio system, replace the meter or obtain a reading then one or more of your bills was estimated based on past use. Sometimes these estimates are close, sometimes they are higher than actual use and sometimes lower. There is typically a correction in the billing cycle following the meter repair.


Is the reading correct?

We have a drive by radio-read meter system. The meter wakes up periodically and listens for an interrogation signal, broadcasts the reading if needed and goes back to sleep. The reading is received by a truck mounted radio transceiver, stored in a database on a laptop, and uploaded to our billing software in the office. The meter is designed to provide an accurate reading or no reading at all and is linked to a specific account using two unique eight-digit identification codes.

Approximately five hundred customers are billed each month and a dozen or less need to be read and entered manually so the chances of a transcription error are quite low. Even though most customers are billed on a quarterly basis, almost all are read on a monthly basis by radio and these extra readings are archived for a variety of uses. We can look at the archive when needed and see when the meter was read and if the readings are sequential.


Is the meter accurate?

Meters are tested as part of the manufacturing process and are required to be within +/- 2% at a low, medium and high flow rates. The flow rates vary depending on the size of the meter but for a typical household meter they are 1/8 gpm, 2 gpm and 15 gpm.

We’ve tested a lot of meters over the years and they typically under-register as they age, especially at low flow rates of less than a quarter gallon per minute. This means that chances are, depending on the age of the meter, less water use was recorded than was actually used. Occasionally a meter will over-register at one of the three flow rates but it is only by a percentage point. Water bills don’t double because of an inaccurate meter.


Have water use habits changed?

Seasonal changes such as irrigation use, kids returning from school, etc. could explain the change in use. We expect residential water bills to be a bit higher than normal for the next few months due to businesses and schools being closed and more people being at home. Individually their daily use hasn’t really changed much, it’s just that the water that was used at work or at school is now being used at home.


Are you a low volume customer?

How meters are configured can affect bills for low volume customers. The totalizer, much like the odometer in your car, on most meters in our system can read down to the hundredth of a gallon either directly or with a wheel for the decimal portion. All of these digits are not used for your bill. Most meters in our system only use the thousands digit and above when sending the reading to the radio read system. Newer meters use the hundreds digit and above.

The precision of the reading can be an issue for low use bills because every use number has a tolerance and could be plus or minus the precision of the read. For example, the actual use for a 10,000-gallon bill from a meter reading by thousands could be as low as 9,001 if the start/end readings were 10,999 and 20,000 respectively or as high as 10,999 if the start/end readings were 10,000 and 20,999. A 1,000-gallon swing can be a large portion of a bill that is only for few thousand gallons.

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Water Department

279 Boston Street

Topsfield, MA 01983


911 -  After Hours Emergency

Office Hours: Monday-Friday 7 AM to 2:00 PM

Highway Department

279 Boston Street

Topsfield, MA 01983


Hours: Monday-Friday 7 AM to 3 PM