if ers ▁at ▁a ▁depth ▁of ▁. ▁Gr ound water ▁stock s ▁are ▁estimated ▁at ▁ 7 ▁billion ▁cub ic ▁meters . ▁ ▁Gr ound water ▁over exp lo itation ▁( over d raft ing ) ▁is ▁a ▁serious ▁problem ▁in ▁parts ▁of ▁Sen eg al . ▁For ▁example , ▁Mont ▁Rol land , ▁ 7 0 ▁kilom eters ▁from ▁Dak ar , ▁used ▁to ▁be ▁famous ▁for ▁its ▁min eral ▁spr ings . ▁Today , ▁vill agers ▁need ▁to ▁dr ill ▁as ▁deep ▁as ▁ 8 0 ▁meters ▁to ▁p ump ▁water . ▁The ▁village ' s ▁ground water ▁was ▁seriously ▁de ple ted ▁by ▁over - ext raction ▁by ▁the ▁min eral ▁water ▁company , ▁which ▁closed ▁its ▁doors ▁recently . ▁Al most ▁ 8 0 ▁percent ▁of ▁Sen eg al ese ▁h ort icult ural ists ▁are ▁located ▁around ▁Mont ▁Rol land . ▁ ▁Dak ar ▁is ▁supplied ▁primarily ▁with ▁water ▁drawn ▁from ▁foss il ▁aqu if ers ▁that ▁run ▁the ▁risk ▁of ▁being ▁over - exp lo ited ▁and ▁cont amin ated ▁by ▁salt ▁water ▁intr usion . ▁Some ▁water ▁is ▁being ▁brought ▁in ▁from ▁the ▁N gn ith ▁water ▁treatment ▁plant ▁on ▁the ▁Lake ▁G ui ers ▁through ▁a ▁pipeline ▁whose ▁capacity ▁was ▁increased ▁in ▁ 1 9 9 9 . ▁Because ▁of ▁growing ▁demand ▁and ▁the ▁need ▁to ▁close ▁cont amin ated ▁bore hol es , ▁even ▁more ▁surface ▁water ▁will ▁have ▁to ▁be ▁brought ▁from ▁the ▁Sen eg al ▁River ▁over ▁a ▁distance ▁of ▁about ▁