Oxidation-Reduction Potential (ORP) What is oxidation-reduction potential? Oxidation-reduction potential (ORP) measures the ability of a lake or river to cleanse itself or break down waste products, such as contaminants and dead plants and animals. When the ORP value is high, there is lots of oxygen present in the water. This means that bacteria that decomposeऔर पढ़ें »ऑक्सीकरण-कमी क्षमता