Focus on San Martin

Focus on San Martin

The Peruvian government is improving the quality of life of urban populations by providing access to reliable and sustainable water and wastewater treatment services through its “Programa Nacional de Saneamiento Urbano” (PNSU). In 2017, the Ministerio de Vivienda, Construcción y Saneamiento awarded the SADE-COSAPI consortium a contract to replace the wastewater treatment plant in the city of Piura, in north-western Peru, on the seaside. This large-scale project was designed to provide for the growth of the San Martin region over the next 20 years (2035 target: 38,000 population equivalent).

The plans 

  • before the construction phase, install a temporary water diversion network for the treatment plant to reduce the existing lagoon to enable the creation of anaerobic lagoons
  • expand the wastewater discharge station located in the town centre and modernise the electro-mechanical equipment (280 l/s with 3 pumps in 2+1 mode)
  • build a 5,700-metre PRV-GRP (Ø 600) connecting pipe between the wastewater discharge station and the treatment plant
  • replace les pumps at the wastewater discharge station CDB-10 (497 l/s with 3 pumps in 2+1 mode)
  • build the new station on the site of the former one, while keeping the station running

 Focus on the work and the new station

  • a connection chamber for the new line, fed by the 3 existing pump lines
  • a pre-treatment station (screens, grit chamber and measurement channel)
  • primary treatment via anaerobic lagoons, consisting of four tanks rendered impermeable with HDPE geomembrane (400,000 m2 for bottom and covering) of approximately 10,000 m2 and depth of 4.5 m each, with removal of biogas and recovery of sludge
  • secondary treatment via anaerobic lagoons in 4 tanks rendered impermeable with HDPE geomembrane, 41,000 m2 and depth of 2.7 each
  • 4 disinfection chambers via chlorination (with chlorine gas) or via lagoons
  • 20 sludge-drying beds of sludge (14.00 m x 25.00 m)
  • a sludge containment lagoon
  • a discharge canal

Official inauguration

On 9 August 2019, Martin Vizcarra, President of the Republic of Peru, inaugurated this wastewater treatment plant carried out by SADE, SEP and COSAPI. The facility then entered a 3-month start-up phase before becoming fully operational.



Located 973 km from Lima, the city of Piura, capital of the San Martin region, is 6th most populated city in Peru.

720 days

Treatment capacity for 270,000 citizens

1.2 m3/second

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SADE - 23-25 av. du Docteur Lannelongue - CS 51450 - 75685 Paris Cedex 14