While demand for water resources continues to outpace supplies, there are many success stories of communities making improvements through conservation. Aquifer storage and recovery (ASR) is a promising method that can save water just like putting money in the bank. Here's how it works: The utility pumps water into wells that are 100's to 1000's of feet below the earth surface. A typical sandstone aquifer has 20 to 30% open pore space to allow water storage. As water is pumped in to the ground the water table rises often replacing water that was previously removed. The process of ASR can be most effective when water is stored during wet years and pumped out during dry years. ASR is being used by southern Denver and many other cities and may be preferred to building new reservoirs -- no water is lost to evaporation when the water is injected back in the ground. The Highland Ranch community is saving a one year supply of water by injecting 14,000 acre-feet of recycled treated water using 25 wells. That also means more water for the South Platte River ecosystem.
I've visited many locations where too much water was withdrawn from aquifers causing the ground to subside and cracked building foundations. ASR could help reverse the trend of water depletion and ground subsidence by increasing aquifer recharge.