the delta area accounts for approximately of the city s area which spreads out in such communes as vinh bao tien lang an lao kien thuy an duong and the south of thuy nguyen the delta area stands between metres metres above the sea level city of hai phong the city is vulnerable to flooding on a periodic basis and tsunamis at any time as well as being threatened over the longer term by sealevel rise localised flooding due to more intense rainstorms precipitation and ocean storm surges