Dampproof flood embankment lifting construction method

The moistureproof flood embankment lifting construction method comprises the steps that upgrading and reinforcing are conducted on an old gate, a seawall is filled and constructed, and the seawall comprises an embankment main body section, an embankment connecting section, an embankment transition section and an underpass bridge section; the two ends of a bridge or a sluice station penetrating through the embankment are each connected with an embankment connecting section, and the other end of each embankment connecting section is connected with an embankment transition section. The dike transition section is connected between the dike connecting section and the dike main body section; two ends of the underpass bridge section are directly connected with the dike main body section; the construction method comprises the following steps: firstly, upgrading and reinforcing an old gate; secondly, carrying out seawall filling construction, namely constructing a seawall dike main body section, a dike connecting sect