New Approach to Detention Pond Evaporation Saves Money
Item #: 20250059
Item #: 20250059
CONTACTS
Implementing Organization: Region Four, Junction Maintenance Station 4468
Implementation Lead: Corwin Christensen, Station Supervisor
Development Team: Corwin Christensen, Brent Jessen, Geordin Gass, Wyatt Barnson
Article Written By: Corwin Christensen
Innovation Council Liaison: Landon Thornton
Innovation Team Coordinator: Quinten Klingonsmith
STATUS
Implementation Date: August 1, 2025
Adoption Status: Fully Implemented
Adoptability Note: Does your pavement drain back into your detention pond? If so, you may want to consider this approach to quickly evaporate excess water.
APPLIES TO
Topic: Maintenance Practices
Organization(s): Central Maintenance / Facilities Management, Environmental Division, Equipment Operations, Region 1, Region 2, Region 3, Region 4
Job Role(s): Roadway Operations / IMT, Transportation Technician
Tags: highway transportation, capital productivity, labor productivity, supplies, employee empowerment, job satisfaction, expenses, expenditures, inventions, ( process improvement ), redesign, facilities, maintenance, pump, sprinkler, pond, salt, evaporate, brine, environmental quality > pollution > air, noise
UDOT maintenance stations store runoff water from washing their vehicles, cleaning equipment, and winter operations so that it does not run off onto public lands and into waterways. If these detention ponds become too full, excess water must be hauled away and disposed of properly, which is expensive. The natural way to handle excess water is to allow it to evaporate. To accelerate evaporation, some stations install sprinklers that spray directly back into the pond, but this process can be too slow to keep up with water usage and storms.
To increase the rate of evaporation, the Junction Maintenance Station (4468) uses its brine pump and inexpensive lawn sprinklers to spray the water from its pond onto the sun-heated pavement surfaces that drain back into the pond.
This practice expands the water’s surface area 3 to 4 times, accelerating evaporation and making it possible to lower the water level in the pond quickly. For example, in July 2025, they evaporated an average of 689 gallons of water per hour over five and a half days (see the linked spreadsheet).
Using this process, the crew can empty their detention basin within 4-6 days for its annual cleaning, and they avoid paying water disposal fees throughout the year. In 2025, they avoided hauling away over 25,000 gallons of water, saving them over $27,000.
An added benefit is that the evaporated water leaves behind salt that can be swept up and returned to their salt pile for use next winter.
This solution is cost-effective because they were able to use the brine pump and hoses they already owned. Sprinklers and fittings were inexpensive, and the system does not take long to set up when needed.
Next Steps: The crew will swap out metal fittings for plastic fittings that will not corrode in the salty water.
The crew noticed that some of the largest evaporation rates occur when the pump runs for a short time, so they are considering running the system in a “pulsed” manner. They would wet down the pavement area, shut off the pump, let it dry, and repeat. This approach would make it unnecessary to run the pump for hours at a time, while also taking advantage of the thermal effects of hot pavement in direct sunlight. With care, this method could be used in areas where the pavement does not run directly back into the pond. Crews would need to make sure they wet down the pavement and stop before creating runoff. In such a case, cleanup would be necessary before the next storm event.
Junction 4468 Detention Pond Evaporation Records (spreadsheet)*
* Note: This link requires Utah.gov access rights and leads to a spreadsheet that includes ongoing records. This spreadsheet is specific to the Junction Station pond dimensions, so it would need to be copied and updated to work properly in other locations.
Evaporation Area 1
Evaporation Area 2
Sprinklers in action
Before - partially emptied detention pond
After - emptied pond
Hose manifold - the 1.5" hose
from the pump drops down to
three garden hoses
Sprinklers - Rainbird sprinkler fixed to a custom stand (3/4" black pipe union at peak, three 2' legs of 1/2" rebar, three 2' spreaders of 1/4" cold rolled).
Note: rebar sticks 1/2" below spreaders for traction. The stands nest sideways for storage.
Suction and foot valve
Winter operations brine pump doubling as the sprinkler pump
Recoverable salt
Brine pump house
Brine pump
Cost Avoidance: $535,215 over 20 years (Aug 1, 2025 - Aug 1, 2045)
Benefit/Cost Ratio: 37:1
*Benefits are estimated net of initial and ongoing expenses. Savings are averaged over the expected benefit life of the innovation. See details.