System and methods for wastewater treatment

A method comprising:

• (i) feeding an untreated fluid comprising sanitary wastewater and/or stormwater to a primary treatment system configured to remove solids from the untreated fluid to generate a primary treated fluid, wherein the primary treatment system consists of a porous filtration media system or a chemically enhanced primary treatment (CEPT) system;
• (ii) oxidizing the primary treated fluid in an oxidation treatment system directly downstream of the primary treatment system, the oxidation treatment system having an inlet configured to receive the primary treated fluid, an ozone inlet configured to receive ozone from an ozone generator, and an outlet configured to dispense secondary treated fluid, and
• wherein the flow of ozone through the oxidation treatment system is controlled to maintain an ozone application rate (OAR) of least 2 mg 03/L-min, such that an effective amount of ozone contacts the primary treated fluid to generate the secondary treated fluid, wherein the secondary treated fluid discharging from the oxidation treatment system has a chemical oxygen demand (COD) removal level of greater than 85%, as compared to the COD of the untreated fluid.