Water Ponding/Management

FranksFarm at aol.com FranksFarm at aol.com
Mon Dec 24 09:26:29 EST 2001


Happy Holidays:)

Some great posts are coming out of this discussion. I'm indebted to the 
authors who care enough to share their expertise on a topic which is 
extremely important to Permaculture.

I have a contour map that includes my farm. I can see where contour lines 
converge on steeper slopes, broaden on gentler slopes. I can see the hollows.

Is there a way to use graph paper to determine, and mark out keylines from a 
contour map?

I'd also like to comment on some of John's post.

<<These are existing drains on your land, correct?>>  Yes!

<<From your description, they are not laid out according to keyline
principles.  So I am *not* talking about using these drains, or saying
they would be moving water where you want it.>>

 I don't think so for they tend to concentrate water, and find easiest route 
down to bottoms, and eventually to creek, and branches. Often dumping water 
where I do not want or need it.

<<I'm saying that if you were to design a system of drains based on
keyline principles, *then* you could intercept water higher up on your
land and move it slowly (reducing erosion and increasing infiltration)
to keyline-appropriate places for ponds, swales, etc..>>

Just what I'm trying to do.

<<Combining this with already mentioned subsoil ripping and rotational
grazing and/or other organic-matter-increasing strategies would be a
comprehensive long-term strategy for drought *and* flooding mitigation
as well as soil improvement, etc. etc.>>

Hmmm.... I understand the need for subsoil ripping, but these are forested 
areas that I'm not planning on using for grazing. The leaf litter from the 
trees etc. built up overtime has improved water retention as they march down 
th slopes. The problem is where the landscape creates natural drainages that 
carry water swiftly away from those areas.

That's the water I'm trying to spread out and hold on my farm. The volumes of 
water, and the speed at which it flows to creek, and branches can be very 
impressive with lots of rain fall. This year too it has become more feast, 
and famine type rain fall. Months of droughty conditions followed by periods 
of heavy rain which turn parts of land into a muddy mess.

<<Not on top of the top of your top ridge - not much water catchment area
up there!  On the broad areas of lower ridges (or lower down sloping
ridges), yes, with water directed there via drains laid out according
to keyline principles>> 

 I thought so:). Somehow I'm not so sure what you mean by lower down ridges. 
Slopes seem to run down from my top ridge steeply at first then more gently 
as they approach base, where land is fairly flat or very gently sloped. There 
are sometimes what I call benches or wider flat areas that were probably 
flattened over years as hills age/erode.

Would these be the same as the ridges of which you speak? From the base of 
the hill it looks more like one continuous rise to top punctuated by a few 
wider, yet still narrow trails that encircle the hills. Some of these may 
have been cut out for logging trails.

<<When I say 'drain', I mean a gentle (1:100 or less) keyline type of
water channel. >> Glad you mentioned this!  The drainage ways I'm talking 
about are generally much steeper especially as they near the ridge. I'd say 
some spots it is 10 or more feet in a hundred. Slopes are actually fairly 
steep at the top, and stay fairly steep till you approach base of the hill 
where are they are more gentle...but still more than 1:100. I'd say around 
3'plus in a 100'.

<<If you have lots of rock close to the surface your subsoil ripping
options would be limited in those areas;>> 

Yes...that seems to be the case. Soil appears fairly shallow. Many of mixed 
hard wood trees don't seem to have very large tap roots, far more surface 
roots.Heavy winds can push over some very large trees.

<<Drains and swales to capture, slow and redirect runoff would still be
an option, combined with the wet-footed plantings and grazing and so on
to increase infiltration and/or transpiration.>>

Lots of vegetation from spring to fall... including many unusual wildflowers 
like trilliums, blue cohosh,wild iris etc.Lots of paw paw trees too under 
shaded canopy...but they don't seem to fruit.( Do they need more sun?) 
Forester tells me soil if fairly fertile.

Lots of wild grape vines ...some 100's of feet long and over 6" thick. I've 
been lopping them down since they can get tangled in the canopy and bring 
down huge trees.These vines seem to favor cherry trees for some reason at 
least I tend to find almost all cherry trees with vines growing up in them.

<<One of the more clever keyline strategies that would go along with your
grazing is this:  map out your keyline drain routes for leading water
out from the concentration points to the drier areas.>> 

Yes...I'm thinking of making the broader base of hills into park like pasture 
for grazing cattle and growing trees. And cattle do walk those fence lines. 
It's interesting to note paths that cattle carve out in pasture. These paths 
don't waste a lot of ground either.

I hope I've given enough information on my woods and hills since I'mtrying to 
incorporate best ideas into a sustainable forestry/livestock operation. I 
want to keep the woods on the hill sides as woods, develop the woods near the 
bottoms as parklike wood/livestock areas. 

I also need to consider best areas for logging roads etc. for minimal 
damage...yet ease of movement.

So much to consider. Sure hope that some of our PC designers might be able to 
help.

Again...really appreciate your responses. And am looking forward to more.

Happy Holidays.   Frank




More information about the permaculture mailing list