Recycled Water Treatment System

• The source water for the Recycle Plant is treated wastewater from the Robert W. Hite Wastewater Treatment Plant.
• The Recycle Plant's current capacity is 30 million gallons/day (MGD) and is expandable to 45 MGD.
• The distribution system includes more than 50 miles of pipe with two major pump stations and dedicated storage facilities.
• Enlarged view of recycled water treatment process illustration above (PDF)

Recycled water treatment process

1. Source water enters the plant and is treated with a biologically aerated filter process to remove ammonia. Air is injected into the base of each treatment cell and the aerated water flows through individual treatment cells containing styrene-based media. The media provide a high specific surface area where micro-organisms attach and act as a filter media for suspended solids removal. This treatment process helps minimize the amount of chemicals needed downstream, and keeps salt levels low in the treated water.
2. The water is then rapidly mixed with sticky coagulants that can capture suspended solids and nutrients.
3. The water is "flocculated", stirred with large, slow-moving paddle wheels. This creates turbulence and increases the contact of solids and coagulant. This allows snowflake-like particles to grow larger and heavier. These large suspended solids then settle out in the sedimentation basin. 
4. The water then passes through filter beds containing a type of coal called anthracite. This stage traps remaining solids.
5. After filtration, the water passes into contact basins where chemicals are added for disinfection and corrosion control before distribution to customers.

See our glossary for explanation of terms.

More Information

Contact Abigail Holmquist at 303-628-7010 or abigail.holmquist@denverwater.org.