Drinking water treatment

La Contraparada DWTP

Drinking water treatment plant
La Contraparada
 

Drinking water treatment is a process to improve the quality of drinking water.

Aguas de Murcia manages the La Contraparada drinking water treatment plant (DWTP) next to the River Segura, in the district of Javalí Viejo. With a nominal treatment capacity of 2000 m3/h, it supplies the city of Murcia and its suburbs. This treatment capacity allows the La Contraparada DWTP to supply an average of 25 % of demand.

The drinking water treatment consists of a number of stages:

  • Preoxidation

    In this stage, the water is treated with chemical reagents to reduce the amount of unwanted compounds and the algae and bacterial load, to improve efficiency in the next stage.

    The DWTP uses chlorine, ozone and chlorine dioxide as oxidant agents and disinfectants.

  • Clarification

    During this stage, organic material dissolved in water and suspended solids are reduced. This is carried out in two stages:

    • Coagulation and flocculation: the process that destabilises particles to produce floccules by adding chemical reagents as coagulants and flocculants.
    • Decantation: the process by which the floccules are separated from water by gravity in the decanters, obtaining clearer water at the top and clarification sludge at the bottom. This sludge is then treated on the sludge line.
  • Post-ozonation

    This is treatment with ozone is used to break down organic micropollutants to facilitate adsorption in activated carbon filters.

  • Filtration

    This consists of running the water through filters containing carbon, a material whose porous surface means it retains pollutants that have not been eliminated in previous stages of the treatment process.

    After flowing through the filtration system, consisting of 12 granular activated carbon units, the water has adequate organoleptic characteristics.

  • Disinfection

    At the end of the process, chlorine is added to maintain disinfection throughout the distribution network and ensure water reaches the supply point in perfect condition.

  • Sludge treatment line

    During the decanting process, sludge is obtained that precipitates at the bottom. This sludge undergoes treatment where first it is concentrated in a thickener and then dewatered in a press filter to be removed by an authorised manager.

Aguas de Murcia take over 73.000 samples a year, which undergo over 233.000 tests for over 300 different parameters to determine the quality of the water supply, in accordance with legal requirements on drinking water quality and in the Internal Control Program .

You can check the water purification processes in your municipality on the SINAC (National Drinking Water Information System) website