Hi Ali,
Alva is a great spot. It works best on a run in tide, but any tide will do. High tide is good because there are more little ponds and puddles to ride in and the river is wider upstream.
There is wind chop surf at the river mouth which is dead onshore so not heaps of fun, but nice enough to break up the monotonous perfect ly smooth water.
Park near the club house and walk across the dunes, rig on the waters edge and ride where ever is least tide effected.
Hope this helps,
