Metered groundwater abstraction increases by 52% in just one year

While abstraction from 244 commercial boreholes has increased by 58%, abstraction from 2,875 agricultural boreholes has increased by 46%

Groundwater from the perched aquifer systems is today almost exclusively used for agricultural purposes
Groundwater from the perched aquifer systems is today almost exclusively used for agricultural purposes

Groundwater extraction has increased by 52% between 2018 and 2019 and by 81% since 2017, official figures derived from 3,119 metered boreholes show.

The sharpest increase in so-called abstraction of groundwater was registered by the commercial sector, which includes water bottling companies and bowsers.

Metered boreholes represent less than half of Malta’s 8,000 registered boreholes and their users are not charged for using the public resource.

While abstraction of water used for irrigation increased by 46% over 2018, the commercial sector has increased abstraction by 58%.

The figures also show that while the vast majority of boreholes extract less than 10,000 cubic metres a year, four boreholes were extracting more than 60,000 cubic metres, up from three in 2018. While three of these boreholes are agricultural, one is used for commercial purposes.   

Moreover, 10 boreholes – including six commercial ones – are abstracting more than 30,000 cubic metres of water each.

The total volume of groundwater abstracted from all metered boreholes in 2019 amounted to 3,832,362 cb.m.

This represents an increase of around 1.3 million cb.m over the volume abstracted from the same boreholes during 2018 and an increase of 1.7 million cb.m over 2017 figures.

Metered abstraction from the 2,875 agricultural boreholes amounted to 2,999,358 cb.m, while that from the 244 commercial boreholes amounted to 833,004 cb.m.

This means that the commercial sector, which includes water bottling companies as well as bowsers, now accounts for a fifth of metered abstraction.

While  on average agricultural boreholes abstract 1,043 cb.m of water, commercial boreholes abstract 3,414 cb.m of water.

But the figures do not account for all the water abstracted by the agricultural sector.

Manuel Sapiano, the chief executive officer of the Energy and Water Agency, explained that figures do not include a number of boreholes which are not metered, including almost all shallow wells (spieri) in the perched aquifer systems.

These wells cannot technically be metered due to the nature of their abstraction equipment – which is either not permanent or located at the surface.

Neither does it include “illegal and hence unmetered abstraction sources, whose existence cannot be discounted when arriving at a total volume of groundwater abstracted”.

The Energy and Water Agency estimates that the total abstraction of groundwater from all aquifer systems amounts to 10.3 million cubic metres: three times the amount of abstracted groundwater which is metered, though still a far cry from previous estimates which suggested an abstraction of over 20 million cb.m.

The correction takes into consideration both registered boreholes and groundwater sources which are not metered, and an estimate of illegal abstraction.

It is important to highlight that this figure of 10.3 million cb.m represents the groundwater abstracted from all 15 groundwater bodies (aquifers), and not just the two mean sea level aquifer systems.

According to Sapiano, this is an important consideration, because a large part of Malta’s traditional irrigated agricultural land is located in areas having access to groundwater from the perched aquifer systems which are largely unmetered.

While the mean sea level aquifer actually floats on a layer of sea water, perched aquifers are contained within the rock formations.

Groundwater from the perched aquifer systems is today almost exclusively used for agricultural purposes.

Commenting on the level of abstraction from individual boreholes Sapiano insists that the “vast majority of users” abstract limited volumes of water from their groundwater sources”.

This situation reflects the highly fragmented nature of agriculture in Malta – and hence the small agricultural land areas which are served by these groundwater sources.

“In fact, by far most agricultural groundwater sources actually abstract less than an annual volume of 2,000 cb.m,” Sapiano says.

When asked what action is being taken to limit abstraction by the few boreholes abstracting substantial amounts of water, Sapiano noted that the current legislation does not impose a volumetric limit on the amount of groundwater which can be abstracted from the respective source.

But regulatory authorities still check users registering high-abstraction volumes in order to advise, where applicable, on how water can be used more efficiently and effectively. Inspections undertaken on high abstractors in the agricultural sector have resulted in such high volumes due to the large size of the agricultural holdings irrigated by this water.

The Energy and Water Agency is currently assessing the temporal distribution of groundwater abstraction from a selected random sample of these groundwater sources.

This analysis will enable a better understanding of how water is used, particularly in the agricultural sector. The first results show different abstraction characteristics, depending in general on the nature of the agricultural activities undertaken by the respective users, meaning groundwater distribution varies according to the cultivation of spring or summer crops in addition to winter crops; if only a winter crop is cultivated, or where permanent crops such as vines are cultivated.

The agency is also using satellite data to be able to cross-correlate groundwater abstraction with land-use, although the small size of agricultural areas (plots) in Malta is providing an added challenge to this exercise. This exercise is intended to develop tools which support regulatory authorities in assisting the agricultural sector in improving the use of abstracted groundwater.

Agricultural boreholes

Under 10,000 cb.m 2,523
10,001-20,000 cb.m 32
20,001-20,000 cb.m 7
30,001-40,000 cb.m 0
40,001-50,000 cb.m 0
50,001-60,000 cb.m 1
More than 60,001 cb.m 3

Commerical boreholes

Under 10,000 cb.m 215
10,001-20,000 cb.m 19
20,001-20,000 cb.m 4
30,001-40,000 cb.m 3
40,001-50,000 cb.m 1
50,001-60,000 cb.m 1
More than 60,001 cb.m 1

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