Oil is expected to start flowing through the Dakota Access Pipeline (DAPL) under Lake Oahe near the Standing Rock Sioux Reservation soon.

Proponents of the $3.8 billion pipeline say it will create jobs in the oil industry, while environmental activists argue the pipeline will damage indigenous land and contaminate the local and downstream water supply. In response, thousands of people have organized sit-ins, rallies, and protests at Standing Rock and other cities since early 2016.

To build on that effort, a growing movement, called #defundDAPL, wants to get at the pipeline's funders where it may hurt them the most: their wallets.

At least 36 banks have provided multimillion-dollar loans to four companies that built and fund the DAPL (Dakota Access LLC, Energy Transfer Partners, Energy Transfer Equity, and Sunnoco). Activists are now asking people to close their accounts at these banks, open new ones at eco-friendly banks or credit unions, and pressure local legislators to divest from the pipeline.

The effort is also a protest against Trump, who signed an executive order in January that revived the DAPL's construction.

The movement started with the North Dakota-based advocacy group Defund DAPL, which has persuaded individuals to divest over $75 million from DAPL-linked banks. Liberal cities, including Seattle and San Francisco, have divested over $5.3 billion.

In late 2016, Defund DAPL started working with local organizers across the country to spread the word online.

Grassroots Action NY, an organization in New York City, created a recent event called Divestment Day that called for people to close their accounts at DAPL-linked banks (in the end, it totaled $250,000 in divestment).

"The main goal is to put our money where our mouths are," Jessica Frisco, the organization's chair, tells Business Insider. "The most frustrating thing is when people go to a rally against the DAPL, but then they go to Citibank right away and put in money. People don't recognize the link, but we're hoping that, with this movement, they start to. Your purchases and capital power need to match what you're preaching on the streets or on Facebook, because money is one of the most important things in our economy and country."

Here are the 36 banks the movement is boycotting: