A type of municipal water rate structure charged by a community water system to those it supplies. The per-unit (1,000 Gallons; HCF; CCF) price of water increases as more water is used, units are typically grouped into blocks or tiers within increasing block rate structures (e.g., Block 1 = 0 to 7CCF $/CCF; Block 2 = 7 to 12 CCF $$/CCF; Block 3 = 12–18 CCF $$$/CCF). Increasing block rates promote water conservation and create water pricing that approaches the true marginal cost of the water supplied. Source: Understanding Your Water Bill | US EPA.