New York Senators Charles E. Schumer and Kirsten Gillibrand and Representative Tim Bishop are among a bipartisan group of Washington lawmakers pushing for a second round of reform of the recently reformed National Flood Insurance Program. Their call for action comes as an increasing number of property owners here and around the country have become aware of steep increases in their premiums, the result of the Biggert-Waters Flood Insurance Reform Act of 2012, which sought to answer the program’s longstanding deficit.