When I originally posted this question, it was due to severe water restrictions being in place in South Australia; rainfall is not as copious as in other parts of the world - we are known as "The driest state, in the driest continent in the world." for good reason.
Harm to the actual environment is also of concern, but it was my intention to discover the best way to use the *least* amount of water, that would achieve safe, archival results without draining our precious, natural resource that is more often than not, in short supply.
Long, hot, dry summers with very little rain the following (or preceding) winter, doesn't allow for gallons of water to be washed down the drain, when it's in short supply. Parklands (usually green in winter and only a little browning in summer) are left to wither as the restrictive time to water is only a couple of hours in the am and pm - with large fines if you attempt to do so out of the allotted timeframe.
So if I can still achieve archival results, without using *any* more water than is absolutely necessary, not only is Adelaide thankful for my prudence with water use, but I'll also be saving $$$ on my water bill and ensuring water is still available for use during the next drought that comes along.