Coming into the game off the back of a three-game unbeaten run, the home side started in confident fashion with Damian Scannell and Peter Gain going close early on.
Just as Charlton threatened to establish a foothold in the contest, Jon Nurse put Dagenham in front with a powerful finish past the stranded Ross Worner after the defence failed to clear their lines.
The sold out away end jeered their side off at the interval, but their complaints only grew louder after the break.
Another spell of early possession for the home side was rewarded when Scannell cut a ball back to Danny Green and the winger blasted his effort into the top corner of Worner's net.
Powell made three substitutions in search of something positive, but Charlton only had an injury time consolation effort from Frank Nouble to show for their efforts, whereas Dagenham continue to climb away from danger.