SPECIAL REPORT SR-2020-04
Performance Evaluation of a Wetland-Type On-Site Wastewater System
Roger W. Babcock, Jr., Danielle Restelli, Trevor Yatomi, Cody Tallman, and Kanoelani Yadao
December 2021, iv+46 pp.
ABSTRACT
The Ridge to Reefs (R2R) Bioreactor Garden (BG) is a constructed wetland (CW) type wastewater system that was evaluated at the East Honolulu Wastewater Treatment Plant (EHWWTP). A pump, plumbing, electronic valves, dosing tank with float switch, and a programmable logic controller (the "system") were fitted to the R2R-BG. The system withdrew screened raw wastewater from the EHWWTP influent channel as influent and treated effluent was discharged into the EHWWTP sewer. The system was designed to provide a total flow of 600 gal/day to the Bioreactor Garden in a manner prescribed by the National Sanitation Foundation Standard 40 (NSF40) and 245 (NSF245) test protocols. The NSF40/245 protocols call for 35% of the daily flow to enter between 6 am and 9 am, 25% to enter between 11 am and 2 pm, and 40% to enter between 5 pm and 8 pm. The protocol calls for a sixteen-week continuous design loading period followed by a series of four stress loading tests over 7.5 weeks and a final 2.5 weeks of design loading.