The District of Columbia Water and Sewer Authority (DC WASA) is implementing a $300+ million digestion project using traditional design-bid-build (DBB) for two component projects, design-build-operate (DBO) for a combined heat and power (CHP) system and design-build (DB) for the fourth component project, the main process train (MPT). The MPT encompasses pre-dewatering, the Cambi™ thermal hydrolysis process (THP), and anaerobic digesters. The economic benefits of this new biosolids program are tremendous compared to the costs associated with the existing lime stabilization system:
- Biosolids quantities will be decreased between 50 and 60 percent, greatly reducing hauling and the risks of the current large land application program.
- Lime purchases essentially will be eliminated.
- A pathogen-free, more marketable Class A product will be produced.
- Digester-generated biogas will fuel gas turbines to produce an estimated 13 MW of power and also produce steam for the THP.
- Greenhouse gases will be greatly reduced.
With these major economic and risk-reduction benefits, it is important to get the project on-line as soon as possible. Therefore, the procurement method(s) selected to move the project forward are critical. Traditionally, DC WASA has utilized the DBB delivery method. This biosolids program includes major movement into alternative delivery (AD) methods. DC WASA’s procurement regulations and guidelines have recently been re-written and approved by the Board of Directors to authorize AD. Specific components of the paper include:
- The Evaluating Team – The Owner’s stakeholder groups, its external AD advisor and the Program Management team conducted a thorough evaluation of delivery methods. Its members include nationally-recognized expert “design-builders” and legal counsel that specialize in AD.
- Expectation to Save Time – By implementing AD, DC WASA expects to get its new facility on-line more expeditiously than it would using a DBB procurement process. •New Procurement Regulations – New procurement policies were enacted by DC WASA in the midst of delivery method selection.
- Alternative Delivery Methods – Various AD methods were considered for each of the four component projects. The evaluation considered the pros and cons of being prescriptive, willingness to accept risk, and other factors.
- Sole-Source Component – DC WASA developed a “determination and findings” that concluded that Cambi is the sole-source provider of the designated THP.
- Risk and More Risk – With each AD method, it was necessary to balance owner-retained risk with transferred risks, evaluating the associated impacts on project costs, the potential for disputes, and the potential for an expedited schedule. •What Did the Market Survey Tell Us? – DC WASA conducted a comprehensive market analysis of the four potential projects, interviewing 15 design builders, DBO firms, contractors, and engineers to help inform the owner’s procurement decisions with the goal of ensuring the maximum amount of competition.