provide nutrient removal efficiencies that would consistently meet the new river standards (5-5-3-1 rule) for wet weather discharge.
New Facility Constructed That new water reclamation facility went on line in 1998 after a "whole lotta work" was done to obtain the property, and then to design, permit, bid, and construct the facility, for just under $20 million. Flow was incrementally diverted to the new plant, and within six months the former 4-mgd, Class B wastewater treatment plant on the North Causeway was decommissioned. By 2010, the commission had: S Developed a sufficient number for its reclaimed water customer base, along with eight local golf course storage ponds. S Modified an existing 13-acre pond for use as a reclaimed water storage and recovery facility, with 27 million gallons (MG) of storage in the upper 6 feet of the pond (Figure 1). S Developed a plan to use several reuse irrigation systems on commission property so that all reclaimed water would be used every day. The control plan was drafted and implemented for all three operating shifts to be on the same page in managing all water supply and demand scenarios. Through the daily, diligent management and balancing of customer irrigation demand and the storage pond assets (and proactive responses to the weather patterns and predicted seasonal variations in rainfall available), the commission has successfully been able to consistently avoid loss of this precious freshwater (i.e., low salinity) resource to the river for many years now. Two key facets of this strategy are the water level in this 13-acre reclaimed water pond and the operating pressure for the reclaimed water distribution system. The pond was already adjacent to the commission’s water treatment facility left over from the I-95 overpass constructed many decades ago, so the costs to convert this were quite affordable. The commission sought assistance from Forever Florida, the state’s premier conservation and recreation lands acquisition program, which approved 50/50 matching funds for the $650,000 cost to install piping to and from the pond’s construct berms and add influent and effluent flow control facilities. The pond water is piped to a connection directly in front of the filters (for filtration and high-level chlorination only) so that the extra water was not pumped into the headworks where it would have upset the foodto-microorganism ratio and detrimentally affected plant performance In the past, the pond was operated in the "nearly full" status, regardless of the season; however, we learned that when heavy rains came, we had no extra storage and had to quickly find a way to distribute surplus water or be prepared to discharge treated effluent into the river. Conversely, in the new strategy we ran at the midlevel point of our operating range. Then, when we were heading toward a high-demand period, we would build the pond volume to be ready for extra supply to the customers (both residential and commercial), with the goal being to avoid rationing. If rainy periods were on the two-week horizon, we'd try and drop the pond level lower than midpoint so that we could accommodate storage of this extra water coming into the pond/demand equation and thereby decrease the chances we’d have to use river discharge. This strategy then incorporated a strategically decreased reclaimed water system operating pressure when demand was high (dry conditions), and increased operating pressure when demand was low during wetter conditions to better manage the resource. This was another dramatic operational change from simply running 75 pounds per square inch (psi) all the time, regardless of the weather. Not only did the more-proactive use of the variable-speed, 250-horsepower reuse pump motors conserve the resource, but it also dropped energy costs by 20 percent ($140,000 in just the first year), which, as outlined in the 2010 article, was the first full year of zero river outfall. With a reliably controlled performance in 2014, we were able to reContinued on page 34
Figure 2. Reclaimed Water Utilization Data
Figure 3. Proclamation from Volusia County
Florida Water Resources Journal • September 2019
33