With 25 acres of constructed wetlands, El Dorado’s new Wastewater Treatment Plant is truly beautiful. Here, you might see fish swimming about, hear birds chirping or watch frogs busily hopping to and fro.

Of course, the wetlands system serves practical uses as well. By using wetlands to support the Treatment Plant, the City is saving taxpayer money. This system is the first of its kind to be used in Kansas.

The new Wastewater Treatment Plant is also an important improvement for the City. The original plant was constructed in 1956 and received improvements in 1977. However, new regulations and growth projections for the year 2020 revealed that the Treatment Plant capacity should be increased to meet an average flow of 3.0 MGD and to treat a peak flow rate of 6.0 MGD.

Professional Engineering Consultants, P.A. (PEC) provided Civil, Mechanical, Electrical and Structural Engineering Design as well as Survey and Inspection Services for this project. PEC worked with the City of El Dorado to study methods for accommodating these new regulations. This study recommended immediate construction of a disinfection facility and an additional study into the potential of using wetlands for treatment.

Pilot Plant
A small Pilot Plant tested the concept’s efficacy for three years before construction and implementation of the full-scale Wastewater Treatment Plant. This project consisted of a two-cell wetlands Pilot Plant that received effluent from the existing El Dorado fixed film Wastewater Treatment Plant.

The objectives of this Plant were to:
• Determine Ammonia removal capabilities during winter conditions
• Determine full-scale sizing requirements
• Determine operation & maintenance requirements
• Determine Capital and O&M costs

New Wastewater Treatment Plant
The new Treatment Plant increased holding capacity to 16.6 MGD, with 4.6 MG extraneous flow basin and 23.9 MG wetland cells. It enables the City to handle anticipated growth and to comply with State and Federal effluent quality standards. The Plant discharges treated effluent into the Walnut River under the requirements of the City’s NPDES Permit.

PEC engineers and the City relocated the existing closed chamber UV system to the new Plant and utilized the existing influent pump station structure. Other important improvements include:
• New pumps and a force main under the Walnut River to the Plant
• A headworks structure, new 1/4” Fine Screens and induced vortex grit removal
• Biological treatment structures with mixers, aeration, clarifiers, RAS/WAS pumps and instrumentation
• New sludge structures containing digester equipment, blowers, centrifuge, sludge holding cells and an activated sludge process (using oxidation ditch technology)
• A site pump station, cascade, scum pump station, reuse pump system and an irrigation system

The Constructed Wetlands System
This wetlands system features a combination of thriving indigenous plants. It is able to naturally treat wastewater by using processes involving wetland vegetation, soils and related microbial life. El Dorado’s constructed wetlands feature a buffer of native grasses and forbs that naturally polish the treated and bypass effluent reaching the cells. The wetlands also serve as a habitat for wildlife.

Additional Features
The new plant and wetlands also provide the following services:
• Effluent site pond and trails for recreational use
• Plant tours, information kiosks and display cases in operations buildings for public education
• Facilities for technical training and/or meetings
• SCADA Control Systems
• Advanced Process for Nutrient Removal

Now, both wildlife and the public will be able to benefit from El Dorado’s new Wastewater Treatment Plant and Wetlands.

PDF FILE OF PROJECT PAGE