WATER AS A SCARCE. Manuel Sapiano Regulation Unit Malta Resources Authority

Transcription

1 WATER AS A SCARCE NATIONAL RESOURCE Manuel Sapiano Regulation Unit Malta Resources Authority

2 Introduction (1) WATER SCARCITY a situation where insufficient water resources are available to satisfy long-term average requirements. It refers to long-term water imbalances, where the availability is low compared to the demand for water, and means that water demand exceeds the water resources exploitable under sustainable conditions. DROUGHT represents relevant temporary decrease of the average water availability important deviations from the average levels of natural water availability and is considered as a natural phenomenon. ARIDITY a natural permanent imbalance in the water availability consisting in low average annual precipitation, with high spatial and temporal variability, resulting in overall low moisture and low carrying capacity of the ecosystem 1

3 Introduction (2) WATER SCARCITY = f(water Availability, Water Demand) WATER AVAILABILITY = f(climatic and Hydrogeologic characteristics) WATER DEMAND = f(demographic and Social conditions) 2

4 Water Availability (1) The climate is typically semi-arid Mediterranean; characterized by hot, dry summers and mild, wet winters. The Mean Annual Rainfall is about 550mm; with the highest precipitation rates generally occurring between October and February. Actual mean annual evapotranspiration is estimated at around 63% of the measured annual rainfall. 3

5 Water Availability (2) 4

6 Water Availability (3) Abstractable Groundwater 13% Runoff 15% Subsurface Discharge 13% Evapotranspiration 59% 5

7 Water Availability (4) 1. No surface waters of economical importance. Utilisation of rainwater runoff is constrained by reservoir carrying-over capacity (est 4Mm 3 ). 2. Fifteen unconfined aquifers with a potential safe yield of 23-25Mm 3 /year. 6

8 Water Availability (4) The "water stress index" is the ratio of a country s total water withdrawals to its total renewable freshwater resources. If we do not consider produced water then the water stress index for Malta should be of the order 100%. 7

9 Finland Sweden Estonia 8 Water Demand (1) inh/km Lithuania Greece Spain Austria Slovenia France Slovakia Portugal Poland Denmark Czech Republic Luxembourg Italy Germany United Kingdom Belgium Netherlands Malta Demographic Characteristics highest population density in Europe

10 Water Demand (2) Water Availability per Capita is the lowest in Europe, estimated between m 3 /cap/year. Malta Cyprus Denmark Poland Belgium Germany A per capita water availability of between 1000 and 1600 m 3 per annum indicates water stress. Availability between m 3 indicates chronic water scarcity, while per capita water availability of 500 m 3 or less indicates a country or region below the manageable capability. United Nations United Kingdom Spain Italy France Netherlands Lithuania Portugal Luxembourg Estonia Slovakia Austria Hungary Ireland Latvia Slovenia Sw eden Finland Water Availability (m3/cap/year) 9

11 Water Demand (3) Need to produce water to meet demand. Desalination (distillation) first introduced in

12 Water Demand (4) DEMAND AND SUPPLY 70,000 60,000 50,000 OTHER INDUSTRY 000m3 40,000 30,000 AGRICULTURE 20,000 GROUNDWATER 10,000 DOMESTIC 0 DEMAND RUNOFF SUPPLY 11

13 Resource Availability 1. No surface waters of economical importance. Utilisation of surface runoff is constrained by reservoir carrying-over capacity (2-3Mm 3 ). 2. Unconfined aquifers with a potential safe yield of 23-25Mm 3 /year. 3. Desalination facilities by reverse osmosis with a capacity of 26-30Mm 3 /year. 4. Treated sewage effluent: current potential availability of 17Mm 3 /year. (Actual use is approx. 2.5Mm 3 /year) 12

14 Conclusion (1) INCREASING SUPPLY Increased use of non-conventional water resources DEMAND AND SUPPLY 70,000 60,000 OTHER INDUSTRY 50,000 TREATED EFFLUENT 000m3 40,000 30,000 AGRICULTURE DESALINATION 20,000 GROUNDWATER 10,000 DOMESTIC 0 RUNOFF DEMAND SUPPLY 13

15 Conclusion (2) MANAGING DEMAND Increased efficient use of water DEMAND AND SUPPLY 70,000 60,000 50,000 OTHER TREATED EFFLUENT 000m3 40,000 30,000 INDUSTRY AGRICULTURE DESALINATION 20,000 GROUNDWATER 10,000 DOMESTIC 0 RUNOFF DEMAND SUPPLY 14

16 Conclusion (3) Average water footprint of Malta: 2216 m³/yr per capita Part of footprint falling outside of the country: 91.7 % Global average water footprint (for comparison): 1385 m³/yr per capita Source: 15

17 Thank you for your attention