#10 | Urban Irrigation Network Management in Aguas de Murcia

Author: Eva Mena (EMUASA)

Since 1974, Murcia has had a red alternative to drinking water for watering gardens, cleaning roads and other ornamental and sporting uses. This Urban Irrigation Network, hereinafter RUR, was built in order to:
– Free up resources for human consumption, rationalizing the supply of drinking water in a supply system such as that of Murcia, which must import water from basins.
– Reduce high costs related to municipal consumption.
– And provide adequately and at all times to “non-drinkable” uses, even during times of drought, through a system that does not compete with drinking water and that guarantees supply, establishing future extensions.

Currently it is made up of a set of boreholes, lifting installations, tanks and general pipe networks for the distribution and supply of groundwater for irrigation of green areas and other alternative uses such as street cleaning. The RUR is made up of 14 wells in operation (Table 1) and 35 piezometers. Some interesting data are:
– Nominal extraction flow: 176 l/s.
– Nominal installed power: 205 kW.

– 65.5% of the area of green areas irrigated with groundwater.

Table 1. RUR surveys.

RUR SURVEYS CHS AUTHORIZATION

S03 Plaza Circular

S09 Cabezo de Torres

S35 La Pólvora

S39 Plaza Bohemia

S47 EL Puntal II

S53 Puente Tocinos II

S56 Monteazahar Beniaján II

S62 Beniaján II

SS01 Juan de Borbón

SS03 Zarandona

SS04 EDAR R. Beniscornia

SS06 Parque Fofó

SN01 Infante Don Juan Manuel

SN02 Senda de Granada

The Segura Hydrographic Confederation (CHS), in November 2012, granted the Murcia City Council (reference file CPA 5/2009), a groundwater concession for garden irrigation and street cleaning, in the amount of 608,719 m3 /year, which is later expanded to 950,000 m3.
The production capacity of the boreholes, according to the lifting equipment installed, ranges from 4 l/s to 35 l/s. The supply pressure in the network, in order to provide adequate operation of the irrigation systems, is around 5 Kg/cm2, being, for the most part, the regulation system installed by means of frequency inverters and a small sector with pressure switches.

The groundwater is fed into the network by passing it through ultraviolet disinfection equipment to prevent possible outbreaks of legionella. Its physicochemical and microbiological quality is regularly controlled through a groundwater quality control program, verifying that its characteristics are suitable for the use for which it is intended.

Likewise, a preventive maintenance plan is also defined for both the distribution network and the facilities themselves. The network is disinfected annually by hyperchlorination in order to maintain its proper state of cleanliness and prevent the appearance of microbial growth.

The data corresponding to the year 2021 are:
– Annual volume of groundwater surveys: 917,176 m3
– Hydrological year volume surveys 20-21: 923,009 m3
– Annual energy consumption surveys: 357,941 kW
– Energy consumption hydrological year 20-21 surveys: 332,640 kW
– Annual energy ratio: 0.3903 kW/m3
– Hydrological year ratio 20-21: 0.3627 kW/m3
– Potable Loading Mouths (Origin Potable Network).- Street Cleaning Use: 35,940 m3
– Non-potable Loading Mouths (RUR Origin).- Street Cleaning Use: 2,336 m3
– Consumption of total load outlets.- Street Cleaning Use: 38,276 m3