The origins of water pollution are numerous, they cause alterations due to their high load of dissolved substances, micropollutants and toxic substances. Many studies have focused on the implementation of remediation measures for these types of pollution. In this work, the case of rivers subject to accidental pollution and the use of reservoirs for its remediation is studied. Two strategies are implemented: the storage of pollutants in the reservoirs and the dilution of pollutants by injecting in the river clear water from reservoirs. Both methods are applied to a river with one reservoir, and their impacts are studied for different flow levels.