The Drinking Water State Revolving Funds and the Clean Water State Revolving Funds have been the foundation of water infrastructure investments for more than 30 years, providing low-cost financing for local projects across America. SRF programs are critically important programs for investing in the nation's water infrastructure. They are designed to generate significant and sustainable water quality and public health benefits across the country. Their impact is amplified by the growth inherent in a revolving loan structure - payment of principal and interest on loans made are available to address future needs