▁res erves ▁and ▁will ▁resist ▁salt ▁water ▁inc urs ion . ▁ ▁If ▁the ▁surface ▁flow ▁of ▁the ▁run off ▁is ▁di vert ed ▁and ▁concentr ated ▁by ▁dra ins ▁that ▁create ▁constant ▁flows ▁over ▁the ▁beach ▁above ▁the ▁sea ▁or ▁river ▁level , ▁the ▁beach ▁will ▁be ▁er oded ▁and ▁ultimately ▁form ▁an ▁in let ▁unless ▁long sh ore ▁flows ▁depos it ▁sed iments ▁to ▁repair ▁the ▁bre ach . ▁ ▁Once ▁er oded , ▁an ▁in let ▁may ▁allow ▁tid al ▁in flow s ▁of ▁salt ▁water ▁to ▁poll ute ▁areas ▁in land ▁from ▁the ▁beach ▁and ▁may ▁also ▁affect ▁the ▁quality ▁of ▁under ground ▁water ▁supplies ▁and ▁the ▁height ▁of ▁the ▁water ▁table . ▁ ▁Dep riv ation ▁of ▁run off ▁Some ▁fl ora ▁naturally ▁occurr ing ▁on ▁the ▁beach ▁head ▁requires ▁fresh water ▁run off ▁from ▁the ▁land . ▁ ▁D ivers ion ▁of ▁fresh water ▁run off ▁into ▁dra ins ▁may ▁dep rive ▁these ▁plants ▁of ▁their ▁water ▁supplies ▁and ▁allow ▁sea ▁water ▁inc urs ion , ▁increasing ▁the ▁salt iness ▁of ▁the ▁ground water . ▁ ▁Species ▁that ▁are ▁not ▁able ▁to ▁surv ive ▁in ▁salt ▁water ▁may ▁die ▁and ▁be ▁replaced ▁by ▁mang ro ves ▁or ▁other ▁species ▁adapted ▁to ▁sal ty ▁environments . ▁ ▁In app ropri ate ▁beach ▁n our ishment ▁Beach ▁n our ishment ▁is ▁the ▁importing ▁and ▁de position ▁of ▁sand ▁or ▁other ▁sed iments ▁in ▁an ▁effort ▁to ▁restore ▁a ▁beach ▁that ▁has ▁been ▁dam aged ▁by ▁er os ion .