ST. LOUIS – It’s that time of year when threats of storms and torrential rainfall are common around the St. Louis area.

When it pours, you might be tempted to place a bucket, barrel or some sort of container outside to collect rainwater. Some people may do this in hopes to reduce their water bills or conserve local waters.

Although the CDC advises against drinking rainwater (due to risks of harmful bacteria), there is no federal law against collecting it and reusing it for non-potable purposes. In fact, rainwater could be potentially used for the following tasks:

  • Watering your garden, lawn or plants
  • Cleaning garden tools
  • Washing your car
  • Bathing
  • Laundry

Since there aren’t any federal regulations against collecting rainwater, it’s left up to states to decide whether to allow it. Some municipalities may also have ordinances encouraging or prohibiting the practice as well.

According to the World Water Reserve, there aren’t restrictions for collecting rainwater in around two-thirds of US States, and some even have incentives to incorporate rain harvesting systems. It had only been illegal in Colorado up until 2016, which has changed its guidance with some carefully-crafted restrictions.

With a storm system ahead for the St. Louis region on Thursday (and likely several more this spring), it’s worth unpacking one big question: Is it legal to collect rainwater in Missouri and Illinois?


The most-recent statute in Missouri to address the collection of rainwater was passed in 2001 and updated in 2018. The state seems to encourage it and promote it as a liberty.

Missouri State Statute 640.648 explains:

“Notwithstanding any law to the contrary, all Missouri landowners retain the right to have, use, and own systems for rainwater collection anytime and anywhere on their own property, including land within city limits.”

Missouri State Statute 640.648

Short answer: It’s legal, as long as it’s not banned in your specific municipality.


The most-recent legislation in Illinois to address the collection of rainwater was passed in 2012. If you plan on it, you might want to think twice about your intentions in doing so.

The Illinois Plumbing Code adopted the resolution passed that year, which explains:

“[Illinois] requires rainwater harvesting collection systems and rainwater harvesting distribution systems to be (A) used only for non-potable uses and (B) constructed in accordance with the Illinois Plumbing Code. Defines “rainwater harvesting collection system” and “rainwater harvesting distribution system.”

Illinois Plumbing Code

According to the Illinois Plumbing Code, it is legal to harvest rainfall as long you don’t collect and store more than 5,000 gallons of it at a time.

Short answer: It’s legal, but somewhat restricted. Also, don’t drink it and check to make sure it’s not banned in your specific municipality.