G'day all
I can well see that because this camping area is ONLY open during school holidays, and is alongside the beach, it will always be a very popular destination.
Should a camper be say, a family of 4 or 5, the numbers of showers & the washing of dishes etc. will create heaps of grey water ... which historically has been allowed onto the ground. Thus, if the council now wants to 'keep it clean' then a restriction on discharge of grey water makes sense.
What I might also suggest to council is that they incorporate an on-site camp host to assist / regulate campers to ensure that all council requirements are followed ~ a twice-weekly visit by the ranger may not be enough