Sarah Zarling has become a close watcher of oil trains since February, when she realized her Watertown, Wis., house was in the blast zone if a train derailed and caught fire.

So when an oil train passed through town Sunday afternoon she prepared to report it to a national network of activists pushing for stricter railway regulations that are keeping close tabs on where and when oil trains are running.

Then she heard a loud boom nearby.

Yelling to her husband to take the kids and flee, she ran to the site of a train derailment near her home in the center of Watertown, population 24,000, hoping to document the crash with photos.

"We so could have been another Lac-Mégantic," she said, referring to the Canadian city where 47 people were killed in 2013 after an oil train derailed and exploded.

One train car leaked oil in Watertown but didn't explode. It was the second derailment in Wisconsin this past weekend ­— the other spilled at least 18,000 gallons of ethanol into the Mississippi River near Alma, Wis. Investigations and cleanups were underway at both sites Monday afternoon, and the twin incidents galvanized several local efforts to bring more oversight to railway practices.

A Minneapolis City Council committee plans to pass a resolution Tuesday morning calling for more and better communication between the train companies and local public safety officials. The resolution has been under discussion for months.

A La Crosse, Wis., group that sued the state over the expansion of rail lines through their community said the weekend's derailments lend more weight to their arguments that environmental risks should be studied. And U.S. Senator Tammy Baldwin, D-Wis., said in a statement that the derailments prove that safety concerns remain as the U.S. House and Senate meet in conference committee to work out a six-year transportation package.

The Alma derailment was the third that led to an ethanol spill so far this year nationwide, according to the Federal Railroad Administration. And the Watertown incident was the fifth derailment so far this year nationwide that led to an oil spill, the agency reported.

Train updates

An eastbound train carrying Bakken crude oil derailed in Watertown about 2 p.m. Sunday, with 13 cars going off the rails, according to Andy Cummings, a Canadian Pacific spokesman. Some 500 gallons of crude oil or less spilled, Cummings said.

Federal officials were on site Monday afternoon to oversee the cleanup and investigation. No cause for the derailment was immediately available.

Thirty-five homes were evacuated. The evacuation order stayed in effect Monday due to some lingering fumes detected near the crash site.

The Alma derailment on Saturday sent 32 cars off the tracks, causing five to crack open, and spill the so-called denatured ethanol. Ethanol generally breaks down quickly but can lower oxygen levels in water and lead to fish kills.

The denatured ethanol in Saturday's spill included between 1 percent to 5 percent gasoline, according to EPA spokesman Andy Maguire. The federal environmental agency tested the river water for traces of chemicals found in gasoline. Initial results were not available Monday.

The tank cars were out of the water by Monday afternoon, he said. Crews have been monitoring the river for clusters of dead fish.

"So far we haven't seen anything," saidMaguire, though he added that spill damage can sometimes take days to appear.

Nationwide, some 910 train derailments were reported in the first eight months of this year, a 4.7 percent increase over the same time period last year, according to the Federal Railroad Administration.

This weekend's ethanol spill was the third this year along a stretch of the Mississippi River, said Irving Balto, a member of the La Crosse chapter of Citizens Acting for Rail Safety, a citizen advocacy group. Eleven Canadian Pacific railway cars, most of them loaded with ethanol, derailed in February near Dubuque, Iowa. Three of the cars caught fire and three fell into the Mississippi River. Six BNSF Railway cars loaded with crude oil derailed in March near Galena, Ill., with two of the cars bursting into flames.

Balto said the group formed last year in response to more oil trains passing through La Crosse. The group sued the state after Wisconsin officials granted approval to Burlington Northern for a four-mile stretch of new track through the city. The lawsuit, which is ongoing, asks for an environmental impact study.

"I'm hoping [the judge] will take a look at these accidents and realize that we need more information," he said.

Matt McKinney • 612-217-1747