Surface water refers to water bodies visible on the earth's surface including rivers, streams, lakes, ponds, reservoirs, and wetlands, as distinguished from groundwater below the surface. Surface water is a primary source for drinking water supplies, irrigation, industrial use, and recreation. Municipal water systems often draw from surface water sources, requiring treatment to meet drinking water standards. Surface water quality is affected by runoff from land, wastewater discharges, and atmospheric deposition. Provincial environmental regulations protect surface water quality through discharge permits, watershed planning, and pollution prevention programs. Climate change affects surface water through altered precipitation patterns, earlier snowmelt, and changing water levels, with implications for water supply reliability and flood risk.