Heavy rains can wash contaminants into drinking, recreational and irrigation waters that can make people sick. Harmful contaminants include human and animal waste, industrial chemicals, oil and other fuels, pesticides and fertilizers. Heavy rains can also result in overflows of combined sewer systems, which are designed to treat both stormwater and wastewater at the same time. During heavy rains, there may not be enough capacity in the system, leading to the discharge of untreated or partially treated wastewater. Flooding can make all of these problems even worse.
Vermont averages over 500 reported cases of waterborne or foodborne illnesses each year. Reported illnesses are more likely during the warmest months and following heavy rains.
Beach closures are common following heavy rains, as sewage or animal waste can wash into surface waters and cause unsafe E. coli bacteria levels for up to 48 hours following a heavy rainfall. During Tropical Storm Irene, 30 public water systems experienced treatment system failures, many private wells were contaminated by flood waters, and over $10 million in damage occurred to crops and farmlands affected by flooding.
Days with very heavy rain (at least 1 inch or more) occur almost twice as often today as they did 50 years ago, and are expected to become even more frequent in the future. More frequent heavy rains combined with warmer water conditions are likely to increase the risk for waterborne and foodborne illnesses in the future.
Here are some ways communities and organizations actively monitor and protect surface waters:
- Learn about how communities monitor and maintain safe recreational waters
- Find out how and why beaches are closed due to E. coli and other health concerns
- View recent combined sewer overflows and other sewage incidents
Here are some tips to help you keep your water and food safe after a flood or storm and during warm months:
- Make sure your water is safe to drink after a flood
- Learn how to prepare for a flood, stay safe during a flood, and protect your health when you return home
- Follow food safety guidelines
- Learn about food and water safety during power outages and floods
- Practice safe food handling and preparation during warm weather
Green infrastructure is a way to manage the water from heavy rains and stormwater runoff that mimics the natural water cycle. Here are some resources for homeowners, businesses and municipalities: