Highly esteemed hydrologists may be hired at the federal or state level of government for their expertise in water-related issues. These jobs may involve detecting and assessing the sustainability of water sources, testing contamination levels in public bodies of water, or devising policies for the responsible use of water and legislation on contaminants. In addition, government and public properties benefit from hydrologists' understanding of irrigation systems, as well as the ability to foresee and lessen the impact of flood and drought.