What factors go into the calculation of my water bill?
The Village of Oak Lawn supplies Chicago water to Tinley Park, Orland Park, Mokena, New Lenox and Oak Forest (referred to as the “customer communities”). Generally speaking, rates for all of the customer communities are made up of three components:
- A rate charged by the City of Chicago for the treatment and delivery of the commodity to Oak Lawn
- A rate charged by Oak Lawn for delivering the water to the customer community
- A rate charged by the customer community to deliver water to its customers
The largest increase of the annual rate increases of the last few years has been for the water received from the City of Chicago, and a smaller additional increase is for the rehabilitation of the Oak Lawn distribution system to feed the Village (see above image).
How does Tinley Park's water rate compare to other neighboring communities?
Tinley Park’s water rate compares well to other surrounding communities, as shown in the below chart:
I've heard the Village uses digital meters. Why are these better than traditional mechanical water meters?
The Village uses digital meters, which have no moving parts. Consumption is measured based on flow past a fixed sensor. This differs from mechanical meters, where water flows through a rotating chamber that spins a dial to record consumption.
Digital meters are better for residents because, when operating at optimal efficiency, they accurately measure flow across all flow ranges and at a high level of accuracy over their entire lifetime, while mechanical meters will under-record use the longer they are in service, which then does not accurately record the flow through the meter. Having digital water meters that are consistently accurate benefits everyone because they ensure all accounts are billed fairly.
The meters that the Village has in its inventory meet the American Water Works Association (AWWA) M6 standards at the time of installation as it relates to water meters and their accuracy.
The Village Board tasked Public Works with providing a service level definition on what it looks for in a water meter. Some of the points are:
- The device will provide a high level of accuracy across its entire expected life.
- Periodic testing will compare accuracy at various time intervals to the AWWA M6 standard for new (not yet installed) meters.
- The device will provide a high level of accuracy across all flow ranges.
- The device will provide equity among ratepayers. Improving overall accuracy of all meters improves fairness across all customers.
- Minimize revenue loss that is the result of meter inaccuracy.
- Avoids rate increases to capture revenue that is lost to inaccurate meters
When did the Village begin using digital meters?
The Village began installing digital meters from manufacturer Severn Trent beginning in 2002. Approximately 28,700 digital meters were installed, and 19,594 of those were still in service as of Dec. 31, 2014.
What are the most common reasons a digital water meter fails?
Digital meters continue to perform accurately and efficiently up until the point of failure. Should a failure occur and consumption cannot be determined, there are policies and procedures in place to come up with a reasonable estimate of consumption that was used to then generate a bill.
Like most electronics, digital meters will fail due to moisture getting into the circuitry, which is also known as water intrusion. Once a meter has failed, it no longer will register any water running through it. A failed or failing digital meter has one of three display conditions: no display, a partial or frozen display, or numbers that increase at an abnormal rate.
These meters, with no moving parts, are designed to maintain reading accuracy over the life of the meter’s battery. The Village’s experience with these meters has shown that failure of the battery or electronics is responsible for the majority of the problems encountered with this type of meter. With these types of failures, the meter may not record consumption at all.
What does the Village do when it receives a report of abnormally high or low water readings?
The Village responds to every report of possible high, as well as low, usage and/or potential problems with meters. The high/low use response process is as follows:
- The Village reviews meter readings and consumption each time a reading is taken. As the readings are processed, an exception report is produced identifying consumption that is unusually high or low.
- If there are no notes on the account as to why use is higher or lower (such as resident advised has new sod, had a leak, etc.), a High Use or Low Use letter is mailed to the resident.
- If a customer calls after receiving the letter, the Village asks if they are aware of any reason for increased or decreased usage. Changes in the number of people, water new landscaping and filling a pool are some examples that might related to a change in consumption that customers may be aware of. If no reason is apparent, the Village mails or provides dye strips to customers to rule out any toilet leaks. Customers are then advised that if no toilet leaks are found to call the Village to schedule an appointment.
- When an appointment is scheduled, the Village generates a High Use Appointment Form for use by the meter technician in checking the meter.
- If the technician finds that the meter has failed, the meter is changed. If the account has not been billed yet, the Village will estimate typical usage for the bill. If the bill has already been issued, an account adjustment is made. If the resident has already paid bill, a credit is issued to the account.
When a high/low-use flag is tripped, this simply means that the reading indicates that more/less water has been used compared to previous history. In each case the Village proactively investigates to determine the cause of the reading and takes appropriate action. It’s important to note that a high or low use investigation also can be initiated by the customer. During this process, the Village reviews the customer’s history and references any rate increases. Sometimes the cost of the bill is higher or lower, but not necessarily the usage (City of Chicago rate increase). The Village then proceeds by sending dye strips to rule out toilet leaks and following the steps outlined above.
My meter failed. Why can't the water meter technician tell me why?
The technician’s task is to identify whether a digital meter is functioning. If it has failed, the technician’s job is to replace it. The technician is not in a position in the field to make the determination of why a meter failed, as there is no way for him or her to accurately determine meter registration/meter flow or what could have caused the meter to fail. The evaluation of the accuracy of a meter requires bench testing, which cannot be done in the field.
It is important to note that all meter technicians are required to report any unusual or extraordinary conditions that are encountered.
How do the meters alert the Village that too much or too little water flow is being recorded?
As readings are processed, an exception report is produced highlighting where the new reading/consumption is outside the expected range based on account history.
On the high side of the exception report, the first “high” alarm is triggered at 1.5 times, and the “double high” alarm is triggered at 2.0 times the usage in the same period in the prior two years. The first “low” alarm is triggered at 0.50 times, and a “double low” alarm is triggered at 0.25 times the usage in the same period in the prior two years.
There has to be a difference of 4,000 gallons or more to have any of the above parameters flagged as an exception. If the customer does not have two years of history, there is insufficient history to spot a trend. In the case of a failed meter, the Village then uses the methodology in the Municipal Code Section 50.024 to arrive at an estimated consumption amount to bill.
My water bill is more than it was last month. Does this mean my water meter is over-recording usage?
This is unlikely to be the case. Consumption can be influenced by a number of widely diverse factors, including weather, changes in family size, preferences, habits, replacement of plumbing fixtures, a running toilet, filling a pool, etc. A larger or smaller water bill does not automatically mean something is wrong with your water meter.
The Village has established protocols for investigating exceptional use. These procedures identify failed meters or validate the exceptional usage. In the case of high usage, in most cases, upon investigation, the Village has found that the customer is aware of the cause/causes of high consumption or is made aware of a problem that is causing high consumption.
If the Village determines that I've been overbilled for my water, what happens next?
Following investigation of reports of abnormal usage, either through the Village’s established Exception Report or as a result of a customer contact, a customer may be issued a credit when warranted by the results of the investigation. Adjustments are based on past history.
If there is no prior history, the Village references Municipal Code Section 50.024, which provides for an estimate of use to be calculated at 85 gallons per capita per day (gpcpd). The 85gpcpd is derived from standards that are used by the Illinois Department of Natural Resources (IDNR) and the federal Environmental Protection Agency (EPA).
Does the Village test water meters?
The Village routinely tests large-size (one and a half inch diameter and larger) meters. Due to the volume of water flow, if a large-sized meter is under-recording consumption, it can translate into significant lost revenues. Now that the initially installed smart meters are approaching the end of their expected life cycle, the Village has started a program to randomly test residential-class meters.
How can I be sure my water meter is working properly?
Verifying your water bill is as easy as checking your water meter at home. Click here to learn how.
Occasionally water meters fail due to moisture intrusion into the electronics, which results in a “short circuit” that is always fatal. It is not gradual and undetectable, nor is it instantaneous, but it runs its course to complete failure in a relatively short time. It has occurred on less than 150 meters of the 28,000-plus meters supplied by the manufacturer.
Public Works investigates all records and reports of high use (as well as low use) proactively, directly and very thoroughly. Adjustments are made to bills and accounts as necessary to reflect fair and equitable treatment of all customers based on industry standards and sound methodology.
What is the Village doing to ensure the water meter failure rate remains as low as possible?
The Village has an ongoing assurance program in place that includes random testing to confirm that our meters are still performing close to the accuracy standards that are referenced in AWWA M6. The M6 standard relates to a new meter being within a rigid tolerance before it is shipped from the factory and placed in service. This is a rigorous industry standard. The meters are pulled on a random basis and from all sizes across our meter stock. On the digital meters that the Village has pulled so far, they have all passed within the tolerance of the accuracy tests for total consumption.
Digital meters offer a significant savings over time, as referenced in the graph above. The next generation of digital meters has an expected life of 20-plus years.
When water meters fail, it is usually because of a dead battery or water intrusion.
What other factors contribute to my water bill?
The Village of Oak Lawn supplies Chicago water to a number of communities in the South Suburban area. A new 40-year water supply agreement has been negotiated that will ensure a supply of water for generations to come.
Because most of the aforementioned communities have grown substantially over the years, it was determined that the water system infrastructure currently in place would not be enough to meet the water needs of future generations. In response, Oak Lawn and its engineering firm, CDM, began construction of a larger system that provides enhanced redundancy through a fully looped system. When finished in 2018, the $171 million system improvements will add dual, redundant feeds, more modern and efficient pump stations, and significantly larger capacity.
As of early 2015, the project is on schedule as it relates to plant improvements, but negotiations are still underway for pipeline easement acquisition. Construction of the pipeline is still on track to be completed by 2018, but as of February 2015, construction has yet to start.
OK. So how do these new water infrastructure improvements impact my water bill?
The cost of the design and construction of the extensive water system improvements are funded by a series of borrowings by the Village of Oak Lawn. Oak Lawn and all of its customer communities, which includes Tinley Park, pay their proportional share of these improvements.
For a typical residential usage of 9,000 gallons per month, the estimated impact of the system improvements amount to less than $5 per month. Each customer communities’ internal rate may also increase on an annual basis to ensure that the rates cover the increasing costs of operations, maintenance and system improvements.
