At the District’s request, the Corps of Engineers releases water from Lake Grapevine Dam into Denton Creek.
The water flows down Denton Creek and joins the Elm Fork of the Trinity River to flow into Ski Lake near Hwy. 114 and N.W. Highway.
Water then flows down a pipeline to the District’s’ plant on Regal Row near Harry Hines Blvd. where it is screened and lifted (pumped) up the plant’s elevation.
Lime slurry and ferric sulfate are added to the rapid mix. The rapid mixer provides mixing of these chemicals with the raw water, causing coagulation or clotting of impurities in the water.
The water then goes to the flocculators, where the coagulation continues, creating a floc particle that becomes heavier than water.
From the flocculators, the water enters clarifiers (settling tanks) where the floc settles out of the water. This settle floc or sludge is pumped out to the sludge lagoons for future disposal.
The clarified water then is run through new granular activated carbon (GAC) filters to remove remaining particles as well as taste and odor problems. The filtered water is then disinfected via the addition of chlorine and ammonia, forming chloramine. Chloramines are used to cut down on the formation of trihalomethanes (THMs) or other disinfection byproducts caused by the addition of chlorine alone.
This filtered water is then pumped to the District’s new ultra membrane filters for final filtration. These filters will filter out all particles 0.4 microns and larger. This provides a physical barrier to Cryptosporidium and Giardia cysts that can cause intestinal, digestive upsets. The filtered water is then sent to the District’s 10 million gallon underground clear well (storage tank), where the water is stored until pumped to the Town of Highland Park and the City of University Park as needed.