Heavy weekend rain sent E. coli levels soaring in the Chattahoochee River, prompting officials to advise people to stay out of the river.

At 3:15 a.m. Tuesday, the E. coli count measured at Medlock Bridge Road was 785, more than triple the count of 235 colonies of E. coli per 100 milliliters of water, which represents a high risk.

According to the U.S. Geological Survey’s Chattahoochee Riverway Project, contact with river water is not recommended when counts climb above 235.

The E. coli count at Medlock Bridge Road before the weekend rain was 76. E. coli counts diminished during the day Tuesday.

“For right now, don’t touch the water,” said Sally Bethea of the Chattahoochee Riverkeeper organization.

“Because you’ve got manholes overflowing, you’ve got cracked sewer lines, septic systems,” Bethea told Channel 2 Action News. “This is just what happens when rain saturates the ground, rolls off the surface and into our river.”

Bethea said Tuesday that it’s common for E. coli levels in the Chattahoochee, as well as in other area rivers, streams and lakes, to skyrocket after heavy rains.

The best rule of thumb, Bethea said, is that if the water is “muddy and turbid after a heavy rain, just don’t touch it.”

She said the high E. coli counts and warnings to stay out of the river should be short-lived. By 7:15 a.m. Tuesday, the level had already dropped considerably to 647. At 10:15, the reading had further dropped to 514.

“With some sunshine and the waters abating, we should be back in a good place,” she said.

While the drizzle and showers persisted early Tuesday, Channel 2 meteorologist Karen Minton said there should be some sunshine by Wednesday and Thursday.

Minton said partly cloudy skies were forecast for Wednesday and Thursday before the next round of rain arrives, just in time for the weekend.

Highs will be in the mid-70s Wednesday and low 80s Thursday and Friday, with overnight lows in the 50s and low 60s.

Minton said there’s a 20 percent chance of rain Friday, increasing to 50 percent on Saturday.

So far this year, Atlanta’s official rain gauge at Hartsfield-Jackson International Airport has recorded 26.92 inches of rain, a surplus of 9.12 inches.