One problem the extreme southern part of the state has had in the past decade is the contamination of water from the drainage of the Valley of Mexico. Mexico City pumps out excess water from the area, as the valley has no natural drainage, to the north into Mexico and Hidalgo states. This water is increasingly polluted and is causing damage to these northern zones. The state is negotiating federal and other help to treat and recycle this water so that it does not do further damage to state agriculture and environment.