Multiple mobile methane leak surveys were conducted on the public streets of Hartford, Danbury, and New London, Connecticut (CT), during the month of March, 2019.  The Hartford survey was done to determine if results from a 2016 survey (Keyes, et al., 2019) were persistent, and surveys in additional towns were done to determine if similar methane leak observations could be made using an identical leak detection approach.  The results show that Hartford continues to be problematic, with approximately 3.4 leaks per road mile observed in 2016 and the same or more estimated in 2019 (4.3 leaks per mile).  This leak frequency compares to the leaks per mile previously found in Boston, Massachusetts (MA) (Phillips, et al., 2013).  Moreover, the surveys and analysis done for Danbury, and New London, CT also reveal problematic leaks, particularly for Danbury with an estimated 3.6 leaks per mile.  Read the 2019 Mobile Methane Report.