Blending Class A+ or Advanced Treated Reclaimed Water with Upper Lake Mary
Surface water augmentation is a form of Indirect Potable Reuse where treated reclaimed water is introduced to an environmental buffer, Upper Lake Mary (ULM), before the blended waters enter the water supply system. Just as demonstrated in the de facto recharge schematic, surface water augmentation occurs unintentionally in countless locations nationwide.
Surface water augmentation is administered through the Arizona Department of Environmental Quality. The City has two Arizona Pollutant Discharge Elimination System (AZPDES) permits, one for each Water Reclamation Plant. The City would need to amend its AZPDES permits in order to legally discharge to Upper Lake Mary without advanced treatment of Class A+ reclaimed water.
Source: Modified from AWWA Potable Reuse 101
How would augmentation have benefited ULM levels?
The graph, below, displays the Upper Lake Mary water levels from 2005-2017. The lake has been at 100% capacity just 4 times in the last 13 years. Surface water augmentation would increase water levels not just for our water supply, but for boating and fishing recreation as well as local ecology. When Upper Lake Mary is full it encompasses nearly 450 acres.
Read about existing Surface Water Augmentation programs.