Is there a way to get this forum to send me an email when somebody replies?

Seems like it ought to be possible but I see no preference for it.

hm… does send me emails…

when in the forum view, click the circle with your initial in it, mine is S,
then click the gear on the top line, then select the notifications menu from the left nav
then select the time under

Automatically track topics I enter

Email notifications work for me. Check your email preferences: Click on your Profile Image in the upper righthand corner, and open the little gear icon, then click emails on the left hand side. The URL will be something like this:

https://forums.docker.com/u/timuckun/preferences/account