Industrial polluters released 849,610 pounds of toxic chemicals into Colorado waterways in 2012, according to a report drawn from federal data.

The most prevalent chemical — nitrates — causes algae growth that leads to dead zones in rivers and streams.

“If we suck all the oxygen out of rivers, then there are no fish and our rivers become lifeless,” said John Rumpler, senior attorney for Environment America, who conducted the analysis. “This toxic pollution is a reminder of why we need the strongest protection we can get under the Clean Water Act.”

The data presented Thursday by Environment America’s affiliates in Colorado and other states comes from disclosures by industrial facilities to the Environmental Protection Agency.

Among the leading polluters in Colorado, according to the report:

• Cargill Meat Solutions Corp. at Fort Morgan — 462,608 pounds of nitrate compounds and ammonia released into the South Platte River.

• Army at Fort Carson south of Colorado Springs — 143,419 pounds of nitrate compounds released into Fountain Creek.

• Suncor Energy in Commerce City — 78,280 ponds of nitrates, dioxins and other compounds released into Sand Creek.

• MillerCoors’ brewery in Golden — 71,000 ponds of nitrates and ammonia released into Clear Creek.

• Climax Molybdenum Co. in Empire and Climax — nitrates, manganese, zinc and other compounds released into the West Fork of Clear Creek and Tenmile Creek.

• Leprino Foods’ plant at Fort Morgan — 19,534 pounds of nitrates released into the South Platte.

• The Western Sugar Cooperative in Greeley — 12,394 pounds of nitrates released into the Cache la Poudre River.

Environmental groups rolled out the report as EPA officials consider extending Clean Water Act protection to thousands of miles of streams and rivers and millions of acres of wetlands around the nation. They contend restoration of federal protection to these intermittent waterways — which had protection before 2006 — will help control the growth of dead zones.

Bruce Finley: 303-954-1700, bfinley@denverpost.com or twitter.com/finleybruce