How much surface water is there in New Mexico?

The most accurate figure for the amount of surface water in New Mexico is approximately 250 square miles. This measurement reflects the total area comprised of rivers, lakes, reservoirs, and wetlands within the state, emphasizing the limited nature of surface water in New Mexico given its arid climate and emphasis on groundwater sources for irrigation and domestic use.

The options that state larger or smaller amounts than 250 square miles do not align with known data and the geographic realities of the region. This context clarifies that while New Mexico does have significant water management challenges, the correct amount of surface water available is around 250 square miles.