A judge has allowed a lawsuit challenging Iowa's management of fertilizer and hog farm pollution in rivers and streams to move forward, handing a significant victory to environmental and community activist groups challenging the state's voluntary farm pollution regulations.Judge Robert Hanson says in a ruling filed Wednesday that Iowa Citizens For Community Improvement and Food & Water Watch may proceed to trial in their effort to prove the state isn't doing enough to clean up the Raccoon River, a drinking water source for 500,000 central Iowa customers of Des Moines Water Works.The lawsuit claims the state has violated the rights of citizens to clean water for recreational and drinking water uses. It asks the court to order mandatory limits on nitrogen and phosphorous pollution and for a moratorium on new and expanding hog confinement facilities.A spokesman for the Iowa attorney general's office says the state is reviewing the ruling and considering next steps.A spokesman for Iowa Gov. Kim Reynolds says she will not comment on the decision.