Soil and water conservation districts may enter into agreements with the United States, as provided by state law, or with the state of Iowa or any agency of the state, any other soil and water conservation district, or other political subdivision of this state, for cooperation in preventing, controlling, or attempting to prevent or control contamination of groundwater or surface water by point and nonpoint sources of pollution. Soil and water conservation districts may accept, as provided by state law, any money disbursed for water quality preservation purposes by the federal government or any agency of the federal government, and expend the money for the purposes for which it was received.