Loading Events

« All Events

Water reuse project of Hersonisos. Reclaiming municipal wastewater for the irrigation water of olive trees

4 June, 2050

Water reuse project of Hersonisos. Reclaiming municipal wastewater for the irrigation water of olive trees

Life initiative (2009-2013)

Waste water source

The wastewater is of urban origin coming from the municipality of Hersonisos located in Northcentral Crete. The wastewater treatment plant receives wastewater from three settlements: ‘Hersonisos’, ‘Piskopiano’ and ‘Koutoulofari’. The wastewater treatment plant is located at the West of the ‘Hersonisos’ town, approximately 0.8 km from the city limits.

Distribution System

The existing network for the distribution of treated water to olive cultivation exceeds 50,000 meters.

Farming system

The wastewater treatment plant’s effluent is used for irrigation of olive groves.

Waste water treatment description

Nutrient removal : Conventional municipal wwtp techniques to remove phosphate and nitrate
Pesticide removal : none
Disinfection : Chlorination and UV disinfection
Suspended solids removal : Sand filtration
Other :


The wastewater treatment plant of Hersonisos is designed for a population equivalent of 40.000. Its average annual capacity is 2,475 m³/day with the maximum capacity reaching 5,297 m³/day.  The total quantity of treated water available for olive-tree irrigation amounts from 3,000 to 12,000 m³ on a daily basis (there is a relevant permit). More than 2,500,000 m³ of treated water is earmarked annually for olive-tree irrigation.

Extent of the agricultural beneficiaries

Served users are over 1,200. The irrigated area reaches 12,000 acres of olive cultivation, with more than 150,000 olive trees. The annual production of olive oil varies from 1,000 to 2,500 tons.


Investment cost for the wastewater treatment plant is € 5,538,224. The reclaimed water is provided to farmers free of charge.

Type of agreement

Scientific results

Papadopoulos, I., Costa, C. N., & Savva, G. (2009). Sustainable Use of Treated Wastewater in the Agricultural Field.

Additional information

Future goals for the municipality of Hersonissos concerning the reuse of treated waste water are:
1. Improvement of water quality at the outlet to enable irrigation of vegetables and generally edible vegetables.
2. Possibility of enriching aquifer from the outflow of the wastewater treatment plants.
3. Harmonization with the requirements of legislation on the re-use of treated water.
4. Improvement and extension of the irrigation network for the use of treated water in more areas.
5. Development of a new management plan for the irrigation network.




Type of initiative
Demonstration initiative, Other
Waste water source
Waste water treatment
Nutrient removal, Desinfection, Suspended solids removal
Farming system
Permanent crops
Application use
Irrigation of food crops to be eaten raw, Irrigation of processed food crops
Irrigation method
Surface irrigation, Drip irrigation
Implementation stage
Full implementation