Colorado flooding
Lauryn McDowell
What’s in the water?

As floodwaters recede following epic storms that hit the region around Boulder, Colo., a week ago, officials are trying to get a grasp on the extent of oil and gas pollution triggered by the deluge.

Oil spills and washed-out chemical tanks only add to the devastation of the unseasonable drenching, which killed 10 people. Another 200 are still unaccounted for, though that number is falling as phone and internet services come back online.

Nearly 1,900 oil and gas wells were shut down ahead of or amid the flooding, but that wasn’t enough to prevent contamination. On Friday, the state’s oil agency said [PDF] it was “tracking five notable releases” of oil and gas and “11 locations with visible evidence of a release, such as a sheen.” It also reported “as many as two dozen tanks overturned.”

More from the BBC:

Officials from the Colorado Oil and Gas Conservation Commission (COGCC) said they were trying to assess the damage from oil and gas spills in the north-central area of the state. …

Some 125 oil barrels (5,250 US gal) spilled from a tank south of the town of Milliken and another Anadarko storage tank near the St Vrain river released 323 barrels.

“In both cases, it appears the oil left the site in floodwaters,” COGCC said in a statement, despite Anadarko’s attempt to deploy absorbent booms around the tank near Milliken.

Rep. Jared Polis (D-Colo.) described the spills a “major public health issue” and told BBC that “the industry, at a minimum, must disclose all chemicals that may be contaminating soil and groundwater.”

The Denver Post reports that nobody yet knows the extent of the pollution:

State inspectors … have fanned along the river to assess environmental damage from toppled oil and gas facilities after the floods.

The flood that began late last week toppled dozens of oil and gas storage tanks and swamped other production facilities at sites in the flood plain. Earlier this week, oil drums, some empty, some full, could be seen floating in the river as far east as Kersey.

What effect will all this have on the state’s fracking industry? It’s telling that some of the wells that were shut down for the floods are already being reopened.

“There’s been massive amounts of growth [in oil and gas drilling in Colorado] in the last two years and it’s certainly expected to continue,” Caitlyn McCrimmon, a senior research associate for Calgary-based energy consultant ITG Investment Research, told the AP. “The only real impediment to growth in this area would be if this gives enough ammunition to environmentalists to rally support for fracking bans, which they had started working on before this.”