Managing Peak Water Usage, Part 2

In a previous post, we told you about three different approaches that municipalities used to successfully reduce water costs:

• peak shifting

• system optimization

• storage increases

We looked at how two communities – City of Troy and City of Novi – convinced citizens to conserve water, one using ordinances and the other education.

Now, let’s take a closer look at the second water management approach: system optimization.

A number of the southeastern communities experiencing large rate increases from their wholesale water supplier, Detroit Water & Sewerage Department (DWSD), already had storage facilities. The problem was that many of the communities’ operational systems had been designed in the 1970s, long before the housing boom of the 90s. Fortunately, engineering studies showed that minor operational changes or moderate capital improvements would reduce the peak flow from DWSD, reducing their water rates.

Controlling the Flow

The City of Northville, City of Oak Park and the City of Auburn Hills all reduced their water costs by making better use of their existing storage tanks. Adding remote monitoring systems, programmed to fill storage tanks during off peak hours, and to keep water pressures constant for users led to substantial savings.

The City of Northville saw a 43% decrease in water rates since installing a supervisory control and data acquisition (SCADA) system and making use of a DWSD water meter signal to maintain a set flow rate.

In the City of Oak Park, engineers modified the existing telemetry system and added a flow meter at the pump station to fill the city’s storage tank during the night. These changes reduced peak water usage by 32%.

The City of Auburn Hills combined minor operational changes with an odd-even grass watering ordinance for industrial and commercial users to cut their peak flows in half: from 3,600 gpm to 1,800 gpm.

System optimization is a smart investment, no doubt…but what about communities that don’t have existing storage? Turns out, adding storage can be a project that pays for itself in savings. Read about it in part 3 of our series on Managing Peak Water Usage.