Moving to tertiary wastewater treatment
We began with a twin focus: plan the startup a new 1.5-mgd biological nutrient removal wastewater reclamation facility and guide rehabilitation of the existing water production and distribution system.
But almost immediately, we added a third: the city's 32 wastewater lift stations, some of which had suffered serious physical, mechanical, and electrical deterioration over a 30-year life span. Minor electrical failures and clogged pumps were leading to frequent alarms. We decided to thoroughly inspect and clean all 32, and discovered in the process that some would need to be entirely replaced. Approximately half were cleaned within a week for $5,000. Alarms immediately decreased by 25% and, after one year, by 80%.
The first 12 months of a new contract are the most difficult because they require both operational (i.e., technical in terms of equipment and processes) and organizational (i.e., psychological as city employees wrestle with deciding which employer to work for and implement the decision) change. Employees appreciated the fact that progress came in steady steps. In fact, as improvements began manifesting themselves team members spent both work hours and time off to clean and refurbish building exteriors and interiors, pumps, piping, floors, and grounds.
In addition to the aesthetics effort, we identified and tackled a list of other tasks: rewriting standard operating procedures, undertaking a thermography scan to find electrical hot spots, developing a repair schedule and preventive maintenance plan, and upgrading the master lift station's electronic controls.
Meanwhile, other team members focused on the intricacies of starting up the treatment operation.
The existing digester and sludge thickening tank were reconditioned without taking the plant off line. The two existing effluent storage ponds were cleaned and disinfected. The rotating biological contactor (RBC) unit was demolished and removed during construction of the new system and plant employees learned how to operate the new Fournier Industries Inc. sludge dewatering system.
We maintained effluent compliance during construction by working closely with the site engineer and contractors. The final element was to the live tie-in of the influent flow from the old plant to the new. We had three concrete saws on hand when it was time to cut the old line and connect it to the new. This prevented a major spill or lift station overflow when the first two saws failed, and the job was completed within two hours without a break in service.
Planning ahead also paid off vis-à-vis employee proficiency with new equipment once it came on line.
We convened detailed and open daily and/or weekly meetings throughout the 120-day period preceding startup.
An early start is particularly helpful in resolving vendor/operator availability conflicts. We scheduled 1- to 4-hour training sessions at least three to four days of each week in the two months before formal startup. This ensured the information remained fresh and gave employees an ongoing opportunity to ask questions about anything that wasn't clear during their previous instruction.
“The learning curve can be steep for individuals without broad wastewater experience,” says Wastewater Reclamation Facility Manager John Sowka, a Woodard & Curran facility manager. “We made the most of frequent training sessions and the presence of the vendor's field staff. You can't ask too many questions.”