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Deep Aquifer Treatment System

Deep Aquifer Treatment System: Making your water shine

Nanofiltration purifies tinted water from the lower aquifer of the Orange County Groundwater Basin, turning it into ideal drinking water.

 

Opened:

2002

Daily production capacity:

7.4 million gallons of drinking water

Well depth:

2,000 feet below ground

Treatment efficiency:

92%

We go deep for pure, appealing water

The best tap water is more than safe — it’s clean, bright, and just plain tasty.

Water from some of IRWD’s sources needs a little extra love to get there. For example: Two thousand feet below us, our deep aquifer produces water the color of iced tea, tinted by ancient redwoods.

That’s where the Deep Aquifer Treatment System comes in. Nanofiltration turns the water crystal clear.

DATS fact sheet

Using nanofiltration technology

Water in the lower aquifer is very high in quality. But until recent years, it was unusable because of a brownish tint.
Purification technologies now make it possible and cost-effective to remove the color.

DATS began operating in early 2002, with two wells that pump water from about 2,000 feet below ground. The water travels through nanofiltration membranes. Because the color molecules are much larger than the water molecules, they are readily filtered out.

The water then travels through degasifiers that remove low levels of methane gas that would otherwise give the water a fizzy appearance.

Frequently Asked Questions

The treatment process has a 92% efficiency rate. In other words, for every 100 gallons of colored water that passes through the facility, 92 gallons of clear water are produced and only 8 gallons of concentrate must be disposed of. The color molecules that are filtered out are referred to as concentrate, which is discharged into the sanitary sewer system.
The Deep Aquifer Treatment System benefits all groundwater users in northern and central Orange County because it helps prevent seepage of colored water into the middle aquifer, which many cities and water districts use for drinking water.