Is there a metric analog to the acre-foot?

Factual Questions
1

I was doing some reading about water use planning and aquifer recharge recently, where the acre-foot as a common unit of volume. For similar discussions out there in the SI world, is there a similar conventionally-used unit of volume (a gigaliter?), or just a whole lot of cubic meters?

2

hectare-meter

3

Hectares and meters are the analogs to acres and feet, respectively, but I’ve never seen reference to a hectare-meter of water. Large volumes of water are simply described in cubic meters or cubic km, depending on how much you’re talking about.

4

And of course an acre isn’t a square unit either, so an acre-foot is really a furlong-chain-foot. :smiley:

5

Wow, I’m not the only one who actually knows what an acre is?

Of course, an acre isn’t inherently tied to a particular shape, so you could equally well say that an acre is 99 inch-miles.

6

Well, yours may not be, but since I prefer not to turn my Ox team and plough too often I’ll stick with having them a furlong long by four rods wide (or by one chain wide if you’re into that new-fangled measurement)… if it was good enough for Edward Longshanks… :smiley:

7

I thought everybody knew that an acre is ten square chains.

Actually, this worked out pretty well for those old-time surveyors. All they had to do was measure the width and length of the area in chains, multiply these together to get square chains, then just move the decimal one place to the left to get acres. Of course, with an irregular area this was a tad more complicated, but the last step was still just to move the decimal one place over.

8

And that’s about the only place in the entire “customary system” where you can do anything by just moving the decimal point. Seriously, every integer up to 12, and every even integer up to 24, shows up somewhere in the conversion factors. And don’t even get me started on 231 cubic inches in a gallon.

9

A new dam near my city uses gigalitres
http://www.actew.com.au/Our%20Projects/Enlarged%20Cotter%20Dam.aspx

10

During the Brisbane floods when they had to do water releases to avoid possible damage to a dam the news reports used gigalitres to describe the amounts of water that was released.