Challenges & Opportunities in the Water Sector (Mauritius) Manta Devi Nowbuth (Dr) University of Mauritius

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1 Challenges & Opportunities in the Water Sector (Mauritius) By Manta Devi Nowbuth (Dr) University of Mauritius

2 The island of Mauritius Mauritius

3 The island of Mauritius Geographical location: between longitude 57 o 17 and 57 o 48 E & latitude 19 o 50 and 20 o 32 S

4 General Information 1/2 DESCRIPTION REMARKS Area 2040km 2 11 times Washington DC Population 1,216,781 latest census (Dec. 2002) Landuse 43% agricultural cover 31% forest & scrubs, 25% built up areas & roads, 1% inland waterbodies Geology Volcanic origin Formed by volcanic activities (10 million to years ago) the island is shaped into a central caldera surrounded by discontinuous rings of mountain ranges ( m) & low undulating coastal plains (100m)

5 General Information 2/2 Climate Tropical climate, summer season November to April& winter May to October Rainfall Varies from 4000mm in the higher elevation (central caldera) to 900mm along the western coasts Overall average rainfall over the island is 2100mm 70% of total annual rainfall obtained during the summer period

Surface water Resources Dense network of rivers Catchment areas vary from 3 to 164km 2, with 2 catchments areas >100km 2 River levels gauged at 100 locations, with 60 continuous

6 Surface water Resources Dense network of rivers Catchment areas vary from 3 to 164km 2, with 2 catchments areas >100km 2 River levels gauged at 100 locations, with 60 continuous recorders 350 River offtakes 10 man made reservoirs with gross capacity 67.36Mm 3 + recent one of capacity 25.5Mm 3 Reuse of treated effluent from St Martin Treatment Plant (Yr 2006 to 2009)

5 Main aquifers Groundwater Resources Contributes around 50% domestic water supply Also exploited to a small extent for industrial and irrigation purposes Salt water intrusion detected along the

7 5 Main aquifers Groundwater Resources Contributes around 50% domestic water supply Also exploited to a small extent for industrial and irrigation purposes Salt water intrusion detected along the northern perimeter Boreholes are on average 30cm diameter and 60m deep, but a few go up to 150m deep Currently about 360 boreholes in operation Exploitation industrial <100m 3 /d - agricultural <200m 3 /d - domestic, on average 2500m 3 /d

8 Water Balance Description Volume (Mm 3 ) % Precipitation Surface Runoff Groundwater recharge Evapotranspiration

9 THE INSTITUTIONAL AND LEGAL FRAMEWORK MINISTRY OF Energy & Public Utilities WMA CEB WRU CWA IA MINISTRY OF Agro Industry & Food Security

10 PORT LOUIS WATER SUPPLY DWS NORTH MAV LOWER DWS EAST MAV UPPER DWS SOUTH

11 Annual Water Utilisation (million cubic metres per year) Purpose Surface Water Ground water Total % Domestic, Industrial, Tourism River-run Offtakes 38 Storage Reservoirs Private boreholes Agricultural Hydropower OVERALL UTILISATION TOTAL WATER MOBILISATION

12 Challenges Water infrastructure (storage capacity) Impacts of Climate Change Water quality Impacts from landuse activities Urbanisation (Increasing demands) High level of Non Revenue Water Institutions working in isolation Fragmented Legislation

13 Ongoing New dams (one under construction & for immediate construction Major developments: Tourism, Road network Challenge- Water Infrastructure Capacity Year of (in million m 3 ) construction Mare aux Vacoas La Ferme La Nicoliere Mare longue Tamarind Falls Piton du milieu Eau Bleue Midlands dam

14 Challenges Climate Change Rainfall pattern changed: Spatially, Flood types

15 Challenges Climate Change

16 Challenges Water Quality Fertiliser consumption is at least 3 times times higher than uses in Western Europe 600kg per hectare With the exception of Nitrate level, quality of water is good.

Challenges - Urbanisation Most recent data compiled by the Central Statistical Office, noted that currently about 44% of the population is living in the urban

17 Challenges - Urbanisation Most recent data compiled by the Central Statistical Office, noted that currently about 44% of the population is living in the urban areas. Water Demand Year m 3 /d , , ,000 Water Demand Year m 3 /d , , ,000 Water Demand Year m 3 /d ,000

18 Challenges NRW Up to 50% Not metered Default metering Leakage Illegal connections

19 Challenges - Sewer network

20 Opportunities Increase storage capacity Implement WDM optimise uses Review the water tariffs Review legislation - Rainwater Harvesting - Desalination along the coastal zones - Water Rights (surface water) Improve sewer network to cover larger area Monitor water quality more frequently Data Analysis & Forecasting Hydrographic network Intensify for more accurate estimates of water resources

21 Thanking you for your attention

ENERGY AND WATER STATISTICS 2016

ENERGY AND WATER STATISTICS 2016 ENERGY AND WATER STATISTICS 216 Introduction This issue of Economic and Social Indicators presents Statistics on Energy and Water for the years 215 and 216. The statistics have been compiled in close collaboration