Rebuilding reserves

Except for fossil aquifers, water tables are replenished naturally by rain, rivers and streams. The rate at which water is withdrawn from aquifers, however, is often far higher than their natural rate of replenishment. In several European regions, for example, aquifer levels are dropping by one to three meters a year due to overuse. Rebuilding aquifers artificially using treated surface water, storm water or wastewater can store water so that resources are available immediately when needs spike.

Restoring and protecting

SNE's recharge techniques minimize and even entirely eliminate the land subsidence risk associated with aquifer overuse. They can also be used to prevent saltwater from seeping in and contaminating coastal aquifers. In practice, aquifer recharge is a three-step process.
  • Treatment of the water before recharge: This step is not necessary if good quality surface water is artificially injected. But it is vital when wastewater or surface water of substandard quality is used. In that case the goal is to recharge the aquifer without jeopardizing the environment or public health.
  • Aquifer replenishment:Injection wells or infiltration basins plus natural gravity can be used to replenish aquifers.
  • Supplemental soil filtration of the water: Once it reaches the aquifer, the water continues to be filtered naturally, with the aquifer serving as a natural treatment reactor.

Technical proficiency

We (us and our international technology partners) already successfully recharge aquifers in a number of countries, including Australia, the United States and Germany. Our reliable plant management and our proficiency in treatment techniques such as clarification and filtration enable us to reuse treated wastewater to recharge aquifers without endangering public health.