too much rain

Hugelkultur-swales-berms - I can see the logic in all of them in the summer season and at other times in the current climate. This same weird climate is about to send a months worth of rain on us in one day when the ground is already saturated with water. Is there a good solution to coping with a deluge of water without washing all your hard work away or passing a field worth of run off on to your neighbour to deal with in the same day they receive a months worth of rain? I'm particularly interested in solutions that fits a couple of acres (I know ponds and lakes come into the thinking but on this scale they too are likely to be overflowing). I realise that established trees will do a lot to keep some soil in place but we have to keep it there long enough in this crazy climate to establish them

Thanks for your thoughts.

A well-designed system of swales and ponds (aka dams) can handle enormous amounts of rain. Geoff Lawton's Zaytuna farm has very large swales which fill with water in the rains, and allow it to gently soak in. I found looking at the map and video of his property to be very helpful. http://permaculturenews.org/2012/06/01/zaytuna-farm-video-tour-apr-may-2012-ten-years-of-revolutionary-design/

For smaller-scale solutions to flooding I recommend volume 2 of Brad Lancaster's "Rainwater Harvesting for Drylands" http://www.harvestingrainwater.com/

We're gradually implementing these structures on our 20 acres where we have two seasonal creeks which in flood provide about 39 million gallons (120 acre feet) of rainwater per hour over the bottom part of our land. There are photos of the structures in my projects thread.

The key is to plan for a safe overflow route for all rain harvesting structures as they will eventually overflow no matter how big. I have to direct water from uphill of our house and workshop right through between the buildings and safely down to the creek. This area has flooded so badly that a fence and a small tree were knocked over, so this is a challenge!

Do your Swales-hugel berms have spillways? Each should spill into the next. We have a similar situation. Zero inches from may to October. 30" the rest of the year. I try and catch as much as I can for the dry months without washing away my hillside.

If your doing the roof rain catching system you could build a cob cistern just below your house to store the run off. That would prevent it from even getting to the swales that are already flooded.

Or you could get one of those huge tanks and bury it?

Other than that, building up as much organic matter in the soil as you can and have as much ground cover growth as possible, while working with the swales and hugel berms.

Swales are really just ponds 1/2 filled with biomass. So you can go ahead and build more to catch hold more water.
But yes at some point that 30 inches of rain in 3months is just going to fill your 30inch deep swale.

you could just turn your plot into a series of 5ft wide swale followed by 5ft wide hugelkultur.
Then your problem would not be having enough space but having enough biomass to fill the swales and hugelkultur

What do you think of this plan?