160 likes | 288 Views
Dealing with seawater intrusion in the Chouka Aquifer , Morocco Fatima Abourrig (ABHSM) , Oussama Ait Raoui ( ABHSM), Henrik Schreiber (BGR), Mariem Boualioua (UIZ), Leonard Stöckl (BGR) IAH Conference Malaga, 23.09.2019.
E N D
Dealingwithseawater intrusion in the ChoukaAquifer, Morocco Fatima Abourrig (ABHSM), Oussama Ait Raoui (ABHSM), Henrik Schreiber (BGR), Mariem Boualioua (UIZ), Leonard Stöckl (BGR) IAH Conference Malaga, 23.09.2019 Regional cooperation in thegroundwatersector in the Maghreb (CREM)
Contents • Introduction of the ABHSM • Constraints associated with the management of water resources • Chtouka plain • Technical cooperation • ABHSM governance
The hydraulic basin agency of Souss Massa (ABHSM) Head office at Agadir Operation area: 28.000 km² (4,5% of the national surface) Population: 2.8 million residents (8% of Morocco; 54% rural, 46% urban) 3 main activities: agriculture, tourism and fishery Irrigatedarea: 148.000 ha
Constraintsassociatedwiththemanagement ofwaterresources • Arid tosemi arid climate • Precipitationbetween 150 and 600 mm/a Theavailableamountofwaterin the SousaMassaBasinislessthan400m³perpersonperyear Thebasinsuffers fromwaterdeficit 2000 1800 1600 1400 1200 1000 800 600 400 Morocco: Jordania 730 m³/person/year Tunisia Algeria Surplus Morocco(730) Egypt Lebanon Stress Need Turkey(2 967) 200 0 Mauritania(fleuve Sénégal) 2017 1970 1975198019851990199520002005 Année 201020152020 Russia(30 299) 0 2.500 5.000 7.500 10.000 12.500 15.000 17.500 20.000 22.500 25.000 27.500 30.000 32.500 Source: United Nations (2006), Aquastat, www.fao.org (Max: >1 Mio m³ / yr)
Constraintsassociatedwiththemanagement ofwaterresources Significantvariationin surface waterimports Irregular rainfall and drought years 2400 2200 2000 1800 1600 1400 1200 1000 800 600 400 200 0 2160 (62-63) Mm³/y 652 35 (61-60) Max Moy Mean Max Min Mm³ 1102 942 1200 1000 800 600 400 200 0 Steadyincreasein water demand 88 50 2000 Drinkingwater 2020 Irrigation water
The Chtoukaplain Very limited surface water resources Strong vulnerability to pollution Growing of agricultural irrigated surfaces Around 3000 farms and 25.000 ha irrigated agricultural surfaces Mostly groundwater (100 Mm³/year) used for irrigation Production in green houses (61%), mainly for the export market
The Chtoukaplain 1988 2003 2014 DevelopmentofgreenhousecultivationintheChtoukaplain (1988-2014) 20 NP(m/sol) Period:1993-2015 Drop:22m Drop velocity:1m/y 25 Steadygroundwaterdepletion 30 Period:1970-1992Drop: 8m Drop velocity: 0.3m/y 35 40 45 50 55 4/692/7312/7610/808/846/884/922/9612/9910/038/076/114/15 Date Piézomètre10/69;x=99007m;y=360865m;z=69.97m 60
Technical cooperation • BGR with Morocco, Algeria and Tunisia under the umbrella of OSS • Mapping marine intrusion • Multiparametric probes in boreholes • On-site phyisco-chemical analyses of well water • Hydrochemical analyses in the laboratory
Technical cooperation Time seriesanalyses • Development of water level and salinitysince 1968 • Sinkingheads, more and more parts lie at or below the sealevel • Water flow direction has changed • Prediction of zones that are at risk of marine intrusion and other pollution
Technical cooperation Monitoring network • ABHSM owns 13 piezometers for water level (2018) • Monitoring of water quality in mostly public wells in the villages • Integration of further public wells to monitor the progress of the marine intrusion has been proposed • 4 new piezometers in collaboration with the ABHSM (drilling finished in 2019)
Technical cooperation Conductivity (µS/cm) Improvementofthemonitoringnetwork • Marine intrusiondetected in twoofthenewboreholes Equippedwithautomaticmonitoringsystemthatmeasuretheconductivity at severaldepths 35000 20 Depth (m) 62 70 7500 date
Technical cooperation Improvementofexistingmonitoringstations • Topographicmeasurementofpiezometerspositionandaltitude • Guideline toimprovethe design ofmonitoringstations • Useofboreholecameratoexploretheconditionoffilterandborehole
Technical cooperation • Groundwatermodelling • Revision andanalysisofexistingmodels • Field investigationandarchiveresearchtoimprovethedatabasis • Improvementofthelatestmarine intrusionmodellingusing different abstractionscenarios • Predictionofthedevelopmentofhydraulicheadsandtheprogresof marine intrusion • Support the ABHSM formanagementactions • Three scenarios: • 1:Increasedpumpingby 2 Mm³/y • 2:Business as usual • 3:Effectof a large-scale project tousedesalinatedseawaterforirrigation
ABHSM governance: Lookforabalancepoint Aquifercontract Development of 100,000 ha with drip irrigation and rehabilitation of 50,000 ha by 2020 (economy of 300 Mm³) • Control of total irrigated surface using satellite images 105 000 ha
ABHSM governance: Lookforabalancepoint Seawater desalination Surface Water DesalinatedWater Groundwater Reducethepresure on theaquifer Now 2021