waterresources

Water resources refer to the available freshwater and related goods derived from natural systems that can be used for human needs and ecological sustenance. They include surface water in rivers and lakes, groundwater, glaciers and snowpack, and to a lesser extent rainfall and atmospheric moisture that can be collected. Freshwater resources are renewable in principle but the rate of replenishment varies; some aquifers are non-renewable in human time scales. Oceans hold the largest share of the planet's water but are not readily usable for drinking or irrigation without treatment.

Spatial distribution is highly uneven. Climate, geology, and land cover create regional patterns of availability; seasonal cycles and droughts affect reliability. Demand is driven mainly by agriculture, which accounts for a large share of withdrawals, followed by industry and domestic use. Efficient use requires measurement, storage, transmission, and treatment infrastructure.

Management approaches include integrated water resources management, which seeks to coordinate land and water use to maximize social and economic welfare while protecting ecosystems. This involves water rights, allocation policies, pricing and tariffs, quality standards, pollution control, and monitoring of quantity and quality.

Key challenges include scarcity and stress in arid regions, pollution from agricultural, industrial, and urban sources, and the impacts of climate change on availability and extremes. Aging infrastructure, data gaps, transboundary river basins, and governance fragmentation can hinder effective management. Emerging solutions include desalination, water reuse, demand management, and improved data systems.

Water resources are central to sustainable development. International frameworks, such as the Sustainable Development Goals, emphasize safe water supply, sanitation, and ecosystem health. Effective governance integrates science, community participation, and cross-border cooperation to maintain reliable access to freshwater while preserving ecological integrity.