Continuous Stormwater Sensing

The Problem

Pollution of water runoff is a huge issue, especially with stormwater. Most water is treated before it joins a body of water. However, stormwater is never treated. Thus, it can pick up many harmful toxins on its journey to a body of water. These toxins can cause many problems in the ecosystem, ranging from harmful algal blooms to poisoning wildlife. Stormwater especially contributes to high levels of nitrogen and phosphorus.

Our Proposal

Our idea is to track the pollution from the source. We propose to put wireless inexpensive nitrogen sensors in drains to track the level of pollution. With knowledge on pollution, we can give people targeted suggestions to improve their behavior. In the worst hit areas, we can introduce additional filters. Our sensor will be based on nitrogen test strips, which are extremely inexpensive (~$0.50 each). The sensor needs wireless connectivity, because we will measure nitrogen levels on rainy days. Additionally, a photo module is needed to take a picture of the test strip. Wireless connectivity will come from a ZigBee module (~$10), and a compatible camera sensor exists for ~$5. Thus, for $15, we can build a durable unit to measure nitrogen. The marginal cost per a measurement is $0.50. Thus, our sensor system is feasible and inexpensive.

We Assume that...

1) We assume that there is variability in the levels of toxins entering in different drains. 2) We assume that local governments allow us to measure levels of toxins in drains.

Constraints to Overcome

When testing nitrate levels in a body of water, we are unable to track down the specific sources of the pollution through many drains. By instead testing specific drains in different areas, we can pinpoint the source of the pollution to a small region, drastically reducing the complexity of the problem.

Current Work

Our primary work is to: 1) Assemble a working nitrogen sensor using the components specified earlier. 2) Validate this sensor. 3) Work with local governments to test pollutant levels at drains.

Current Needs

Our project would benefit from additional people with expertise in hardware and mechanical engineering.