With private investors poised to profit from water scarcity in the west, US senator Elizabeth Warren and representative Ro Khanna are pursuing a bill to prohibit the trading of water as a commodity.

The lawmakers will introduce the bill on Thursday afternoon, the Guardian has learned. “Water is not a commodity for the rich and powerful to profit off of,” said Warren, the progressive Democrat from Massachusetts. “Representative Khanna and I are standing up to protect water from Wall Street speculation and ensure one of our most essential resources isn’t auctioned off to the highest bidder.”

Water-futures trading allows investors—including hedge funds, farmers and municipalities—to trade water and water rights as a commodity, similar to oil or gold. The practice is currently limited to California, where the world’s first water futures market was launched. So far, the market hasn’t taken off, dampened by the reality that the physical trade of water in the state has been limited. After a couple of wet years in California, the price of water futures has also plummeted.