The City of Dickinson experienced significant growth beginning in 2005. The population increase, aging equipment, and the need to address more stringent nutrient limits for future regulations led the City to evaluate a mechanical treatment facility option. 

Apex was retained by the City to plan, design, and administer the construction of a new, state-of-the-art wastewater treatment facility.

Preliminary Engineering Report

 Apex was tasked with completing a preliminary engineering report (PER) for the City to forecast wastewater flow and loading projections for a 20-year planning period. The PER evaluated innovative treatment technologies including: 

• Integrated fixed-film activated sludge (IFAS)
• Moving bed biofilm reactor (MBBR)
• Membrane biofilter (MBR)
• Biological Active Filter (BAF)
• Tertiary Filtration
• Pre-thickened Membrane Aerobic Digestion (PAD-K) to address some of the state’s most stringent effluent nutrient regulations

IFAS System

An IFAS system was recommended for the liquid portion of the WRF to biologically reduce total phosphorus and total nitrogen in plant effluent prior to discharge. It also provided consistent, quality effluent intended for two million gallons per day of reuse in a diesel refinery.

PAD-K Aerobic Digester

A membrane thickened (PAD-K) aerobic digester was selected for biosolids stabilization, and liquid land application was utilized for biosolids disposal. 

Design

Due to the rapid population expansion, Apex utilized a flexible, modular approach when designing the WRF to prevent an unnecessarily large facility, which would have been expensive to construct and difficult to operate. The flexible design allowed the City to double the capacity of the WRF in the same footprint, thereby maximizing City-owned property while allowing for future expansion.

Apex incorporated wet-weather flow diversion into the design of the facility to divert high flows away from the new WRF to the City’s existing stabilization ponds, thereby utilizing existing infrastructure to more economically and effectively manage wet-weather flow events. 

On-schedule startup of the new facility occurred in June 2014. 

Uniqueness of the Project

The Dickinson WRF is the first of its kind in North Dakota, utilizing innovative biological treatment technology and biosolids thickening. The facility will treat water to some of the most stringent effluent standards in North Dakota to date. The state-of-the-art facility treats an average daily flow of 3.65 million gallons and serves as a regional wastewater treatment location for the City of Dickinson, surrounding communities, area industries, septage haulers, and crew camps. 

The WRF conserves potable water by providing reuse water for irrigation, refinery process water, oil field fracking water, and facility plant water. 

Funding

• State Revolving Funds
• Oil Impact Grants
• Sale of reclaimed effluent for reuse purposes