Yes. Deep Creek loop using the Heysen trail is a great short walk.
We did it as a variant to the through walk from Cape Jervis to Tungkallilla as reported here:
http://bushwalk.com/forum/search.php?keywords=Next+day+we+placed+the+cars+&t=7641&sf=msgonlyI also took a group of keen young lads through last Dec on a wet day. Creek was still flowing and the place was still green.
The key to crossing the Deep Creek mouth was to realise that even if the tide is in, the lagoon is very shallow and can be easily waded if the entrance rocks are getting covered by wave surges.
It has been a very wet start to the year here in SA. My local recordings have the rain almost at the annual average, and it is only July.
Been at Morialta a few weeks running now, and have turned back at the upper track crossing on the way to 3rd falls due to the level of the stream there.
A few shots from back in Dec then:

- Deep Creek mouth at lower tide level and a small creek flow.

- Deep Creek valley from the wonderfully steep climb out.