How GIS helps cities stretch limited water supplies

Wed, 2014-10-22 06:00 -- Kevin Ebi

About one-fifth of the world’s population doesn’t have enough water, a problem that’s only getting worse between droughts and continued population growth. But until the rain returns or other sources are found, geographic information systems (GIS) can help cities better manage the water they have.

When every drop counts, it’s important to know where every drop is and where it’s going, which is a bigger problem than it might seem. It wasn’t long ago that Bangalore, India couldn’t account for half of its water.

This is the kind of insight GIS can provide. Council Lead Partners IBM and Itron, for example, have both built upon Esri’s GIS mapping technology, allowing planners to track water over time in various areas. Among other things, this can help them understand exactly how groundwater systems work, and set use policies to protect them. They can also use GIS to know where they should concentrate their conservation efforts or to crack down on chronic water wasters.

Finding new supplies
Some communities have even used GIS to find new sources of water. South Australia, which has also been battered by drought, was one of the first to use GIS models to more effectively collect and reuse storm water.

During heavy storms, rain falls faster than the ground can absorb it. By using GIS models, planners were able to find places where they could most efficiently collect storm water, harvesting water that would otherwise go to waste.

While that runoff isn’t drinkable, it can be used for industrial purposes, in toilets, and for some consumer uses, such as car-washing. But by removing that demand from the tremendous pressure on the potable supply, there’s more water left to drink.

Understanding where the water is going
There are two sides to the water equation. If there is less available water for each person, one solution is to try to get everyone to stretch their water further.

A growing number of utilities are working on this by combining smart meters with GIS. Having a real-time view of where the water is being used helps the utilities spot problems immediately and understand where the biggest water consumers are.

By seeing who is using a lot of water and when, utilities are able to focus their conservation education efforts where they will have the biggest impact. And by seeing a sudden, unusual spike in usage somewhere, they can learn of leaks as soon as they happen before too much water is lost.

Tracking water wasters
While no one likes to be told when they can’t water their lawn or wash their car, such measures have become key fixtures of conservation efforts when the water supply is especially tight. But enforcement can be an ordeal. Austin, Texas is using GIS not so much to track its water supply, but rather the people who waste it.

The city’s water utility developed an app that greatly reduces the time inspectors spend recording violations. When they see a violation, they can open an app that streamlines the enforcement process. It uses GPS in the tablet or smartphone to automatically record the location. The officer can also take pictures, add notes, or specify special considerations, which are automatically attached to the GIS record.

Using GIS, agency managers can see where the violations come from or if certain businesses or people are responsible for many of them, allowing them to take action or concentrate enforcement efforts.

Austin says the technology has made its enforcement officers 50% more effective, which combined with extra revenue from fines, has saved it $600,000 in overtime and temporary staffing costs. Hopefully, the more efficient enforcement has also saved it some water.

Importance of GIS
The Council's Smart Cities Readiness Guide, available free to registered members, outlines the value of cities having access to a central GIS – and not only for the water-related benefits mentioned above. A GIS that maps all of a city’s assets and location information is a big contributor to what makes a smart city smart. Applications of GIS technology run the gamut from mapping crime data to aid public safety work to maximizing traffic flow and sharing helpful traffic maps with the public. Download the Readiness Guide to learn more >>