Where to drain pool water when a pool is emptied

The ACT’s four conditions for the sewer

The ACT’s utility writes the emptying rule the plainest. Icon Water’s acceptance guideline for discharges from pools allows a domestic pool into the sewer only where every one of these is true:

the pool is being emptied so that major repairs or repainting can be done;
the sewer is the only drain the property has;
pumping the water to the environment or to stormwater is not a workable option;
and the water being discharged meets the quality requirements the utility sets.

That list is worth reading twice, because it is the only one of these draining rules that names the reason a pool is emptied. Major repairs or repainting is the ACT utility’s own phrase for a renovation that empties the pool. Not every renovation empties a pool, and nothing in these rules says otherwise.

One question, three answers

Move west and the answer changes, and the reason is that each utility is writing about a different pipe.

SA Health writes about the filter. In sewered areas, the water used to backwash or rinse the filter must always be disposed to sewer. In unsewered areas, SA Health points to the Environment Protection Authority’s fact sheet on the disposal of swimming pool backwash water rather than setting a rule of its own.

The Water Corporation in Western Australia writes about trade waste, and its answer runs the other way: for a domestic pool or spa, backwash and drainage are not classed as trade waste, and they may not go into the sewer. The same page sends the owner to the council for the alternative, since the Local Government Authority is where the disposal options come from.

Sydney Water writes about the stormwater drain, and its rule is a refusal with a reason attached: water from a pool or spa may not go into the stormwater system, because it is chlorinated and needs treatment. What follows is without conditions: chlorinated water goes to the wastewater system.

Resolving the three answers

Set side by side, the three sentences look like a disagreement, and one reading removes it. Each rule is scoped to a pipe and a state, and none of them is a general answer:

South Australia’s sentence is about the backwash water from a filter in sewered areas, and it names the sewer as the destination.
The Water Corporation’s sentence is about trade waste classification, and it says domestic backwash is not trade waste, and it says that backwash and drainage may not go into the sewer.
Sydney Water’s sentence is about the stormwater system, and it gives the reason the water is refused there: chlorination.

So a renovator reading only one of them would get the wrong pipe. The scope is the rule: each sentence belongs to its own utility or department and to no other.

The states, one by one

The ACT: Sewer only if the four conditions above all apply; the alternative routes have to be not feasible, and the discharge has to meet the quality requirements.
South Australia: Backwash water to sewer in sewered areas, always; in unsewered areas, the EPA’s fact sheet on disposal of swimming pool backwash water.
The Water Corporation’s area (WA): For a domestic pool or spa, backwash and drainage may not go into the sewer, and the council is where the disposal options come from.
Sydney Water’s area (NSW): Never the stormwater system; chlorinated water goes to the wastewater system. A very large pool brings one more step: a pool 50 metres long, the length of an Olympic-size pool, needs a trade wastewater application through Sydney Water’s Tap in service.
Queensland: Queensland Health’s private spa guide, for spa water: dispose of your used spa water in accordance with local laws, and enquire with your local council if you are not sure of the laws that apply in your area.
Victoria: The Victorian pages cited here name no rule for domestic pool water disposal, so none is stated.

The water the filter uses all year

The emptying is not the only time water leaves a pool. Icon Water, writing for ACT pool owners, puts a figure on the routine: a sand filter needs backwashing, and that can use up to 8000L of water in a year. The same page sets the interval and the stop point: the interval is once every 4 to 6 weeks, and the stop point is when the glass goes clear, because backwashing for longer wastes water. One more practice belongs with them: overfilling a pool stops the filter working properly and sends water over the edge.

The way back in

Before the refill, Sydney Water asks one more question. It asks that the Water Wise Guidelines be checked before any water is removed, to see whether refilling the pool needs a permit. Applications are considered one by one, and the answer is narrow on its face: a permit is approved only where the drain and the refill cannot be avoided.

So the water goes down once, through a rule written by the utility or department for its own pipe, and, in Sydney Water’s area, back under a permit granted only where the drain and the refill cannot be avoided. The water that comes back has numbers of its own, and the refill guide holds them. While the pool is empty, the parts to check are in The potty-style skimmer, from ordinary part to national ban, and who may do the work is in Who may do each part of the work?