Demonstration and performance analysis of on-beach public toilet with a decentralised modified French vertical flow constructed wetland and ex situ electrochlorination integrated treatment system

India's concern about wastewater generation outpacing the centralised treatment capacity has increased significantly. This study demonstrated an on-beach public toilet equipped with a sustainable decentralised treatment system in Goa, India. The research gap of the number of toilet users, freshwater demand, and wastewater (WW) generated per day in India was documented. The treatment system consisted of a modified French-type vertical flow constructed wetland (MVFCW) and electro-chlorinator. The first and second stage MVFCW were an unsaturated and saturated type, respectively. The onsite beach bore well water with a chloride concentration of 8464 ± 415.18 mg/L was electrolyzed for 1 h at 40.49 Am−2 to perform ex situ electrochlorination disinfection. The MVFCW effluent was disinfected with 2412.50 ± 278.61 mg/L of chlorine (Cl2) generated at a disinfectant dilution ratio of 1:300 (Cl2:WW) to ensure less than 5 mg/L residual Cl2. The average daily toilet users, freshwater usage, and WW generated were 96 ± 17.02, 1381.38 ± 380.35 L, and 1407.98 ± 611.8 L, respectively. The integrated treatment system treated 1,400 L/day. The integrated treatment system achieved an average percentage removal of 93.38 ± 0.38% chemical oxygen demand, 79.18 ± 1.55% NO−3, 98.45 ± 0.22% total ammoniacal nitrogen, 93.13 ± 1.19% PO4−3, 87.28 ± 0.2% total suspended solids, 83.09 ± 1.16% total organic carbon, 80.22 ± 0.87% total carbon, 80.05 ± 0.12% inorganic carbon, and 100% coliform. The cost of power consumption was 0.17 INR m−3.