IoT forging new pathways to innovation

Taking control of storm water

Cary, N.C., is a suburban community in the Research Triangle area with a population of about 175,000. As part of a plan to create a more adaptive, distributed leadership culture in the local government, a concerted effort was made about 6 years ago to better integrate information systems and provide access across all departments. One area of concern was storm water management. Up until that point, the primary focus of storm water management was on issues such as right of way and infrastructure, and a proactive approach to flood management had not been taken in a significant way. Information about rising water, for example, was received mainly from citizens’ reports submitted on an ad hoc and often emergency basis.

In addition to improving data sharing across departments, the major culture change also promoted broad involvement by stakeholders. “We established a storm water working group that included professors, storm water planners, and citizens who were experiencing flooding,” said Danna Widmar, assistant town manager in Cary. “We were fortunate to have access to some of the foremost experts in storm water management, ranging from academics to practitioners.” The resulting proposal was unanimously accepted by the town council. The approved plan included development of models for managing storm water based on implementation of an IoT sensor system. “We started with a small watershed in Cary called Walnut Creek, which feeds into Raleigh, then continued our work in Swift Creek, a much larger watershed in Cary,” continued Widmar. “We have over 30 sensors, including rain gauges and stream sensors that detect water level, rainfall amounts, air and water temperature and take photos on demand,” Widmar added. The system can trigger alerts if the water level is unusually high in a particular location, which may result from a blockage or rising flood waters.

At the threshold water level, the alert can then automatically send service requests that deploy field staff to investigate and resolve the problem. In addition, citizens can now access information through an open data portal. Along with improved storm water management, the town also wanted to ensure that development would not create additional problems and to protect the watersheds in the community. The data is used by Cary and other government partners. “We try to prioritize work on the most important issues,” Widmar explained, “so that citizens who are most impacted can be prepared and protected.”

The data is stored in Microsoft’s Azure Cloud with predictive analytics by SAS, which is used throughout Cary’s government departments. Cary now has a year’s worth of data from its storm water sensors. “Over time, we will be able to look at historical data and make better predictions,” noted Widmar, “and we can continue to refine our models based on additional data.” The town is using the Storm Water Management Model, which simulates the runoff quality and quantity of water. As new data comes in, the model is refined to more specifically reflect the conditions in Cary’s storm water system. The IoT sensor system is also scheduled for expansion into a third watershed in the coming year.