Water Ponding/Management

John Schinnerer eco_living at yahoo.com
Wed Dec 19 03:53:00 EST 2001


Aloha,

Here's the Keyline web site:

http://www.keyline.com.au/

They say the latest print edition (1993) is out of print and offer to
sell you an e-book to read on your computer :-p.  I just bought two
printed copies of th 1993 edition from Rodale this past summer, so I'd
call Rodale quick and get a printed copy if they're still available.

> I'd like to build some ponds on the sides of those hills but am not
> sure how to find best places.

Ideally ponds go on broader areas of ridges and/or saddles, or as
nearly as possible, where it's flatter and easier to build a stable
pond with good work/volume ratio.  I find this hard to describe well in
text alone, but if you get the book or look at some of the web site
content and know how to read topographic maps, and then look at your
own land, I think you'll get the idea more quickly.  Bear in mind that
the terrain Yeomans is working with in Australia is *quite* gently
rolling, at least compared to the hilly N. American landscapes I'm used
to (Western states ranges, Vermont, etc..  So you'll see dams in places
in his illustrations that would probably not be suitable to steeper
terrain.

> I was simply going to find a deep drain near a
> shelf that could be dammed up. 

If you mean damming up a gully/valley, this is the last/worst choice
for where to build a pond.  
Basic reasons:  
* most likely to blow out (it's right where water naturally
concentrates the most, and likely fast-moving water too... :-o)
* fastest to fill in - with soil, that is (inflow comes from
gully/gullies where most erosion is taking place).
* least water volume stored per dam volume (you get less water volume
per unit of earth moved for the dam than most any other location; in
other words, less water stored for a given dam size than other
locations).

> Heavy clay soils down here hold water very well. 

You mean on the surface, right?

> And often such soils are not 
> very deep. Only a few inches of top soil in many areas. Bottoms oth
> are fairly deep, and for the most part well drained.

So do you have a clay layer over something more permeable, or rock,
or...?  I'm wondering if subsoil ripping to let water through a shallow
clay layer might help...but what's underneath your clay?

> Lower pastures as suggested were probably just bull dozed and seeded
> without much leveling so there are numerous fairly gentle undulations
> that lead to 
> ponding. Additionally there are numerous wet weather springs below
> the surface.

I don't know enough about your soil/geology...sounds like the combo of
clay surface soil and water concentration are creating rapid runoff and
 these boggy surface areas in the low spots?  Slowing the water down
and spreading it out (with keyline techniques) might help, if areas it
currently runs off of can absorb and hold it in the soil (most
efficient storage location) and/or ponds.

cheers,
John S.



=====
John Schinnerer, MA
--------------------
- Eco-Living -
Cultural & Ecological Designing
Food - Shelter - Community
john at eco-living.net
http://eco-living.net

__________________________________________________
Do You Yahoo!?
Check out Yahoo! Shopping and Yahoo! Auctions for all of
your unique holiday gifts! Buy at http://shopping.yahoo.com
or bid at http://auctions.yahoo.com



More information about the permaculture mailing list