MINOT, N.D. — The Souris River began a long, slow retreat in Minot on Sunday, leaving behind an arduous rebuilding job for more than 4,000 homeowners and hundreds of business operators, most of whom lack insurance to pay for it.

Because they don’t have coverage, federal assistance could amount to as little as a few thousand dollars apiece. Loan and grant programs will provide some help, as will an emergency relief fund just being set up.

Still, there was at least one ray of hope: State lawmakers might be able to lend a hand, thanks in large part to North Dakota’s oil boom, which generates $1 billion a year in tax money and has helped shield the state from the worst of the recession.

Few people in Minot carried flood insurance — only 375 homes in the flooded areas, said John Ashton, a spokesman for the Federal Emergency Management Agency.

Mike and Jodi Picard checked with neighbors when moving into their house less than two years ago and found that just one had flood insurance. The river was a quarter-mile away, and the prevailing opinion was that “we were not in a floodplain anymore” after a 1969 flood led to construction of levees and straightening of the river channel.

The Souris topped out Sunday nearly 2 feet below projections heading into the weekend, and it appeared damage might not extend beyond the homes and businesses that took on water Friday.