C6.2 Regulations for water quantity
Regulatory instruments for ground and surface water quantity control include permits for ground and surface water abstractions. The quantities permitted may reflect seasonal needs.
Usually, general rules (for example certain volumes of abstracted water) determine when a permit is needed and when it is not. General rules may forbid or limit abstractions for specific waters or under such specific conditions as times of drought.
Control of water quantity and quality are closely linked. In surface water systems, abstraction reduces flows and hence the ability of a river or stream to absorb and degrade wastes. It therefore decreases the ability of a river or stream to maintain desirable ecosystems.
Illegal or uncontrolled abstraction of groundwater for agriculture, industry and household use is widespread in many areas (e.g. peri-urban settlements) and can have serious implications for groundwater quality. Permanent abstractions above the recharge often result in serious saline intrusion in the productive aquifers, making the water unsuited for domestic or irrigation purposes.
Effective regulation of water abstractions requires information on the available water resources and the present abstractions. Moreover, sufficient institutional capacity must be available to apply the different tools for compliance monitoring and enforcement appropriately. (B1.6, B2.3) The need for institutional capacity should receive attention in the water resources assessment (C1) and policy and planning stages (A1).