Water catchment in rocky soil

Good day everyone! Every rainy season a considerably large area drains through the lower portion of my property. I figured out I could do some earthworks and catch the runoff so I could use the water during the dry season. Doing some test pits we found out that soil in that particular zone is about 1m deep before reaching huge boulders and rock. It would require big machinery to do any significant digging and I think the investment would be way too much. Any suggestions? Maybe creating a shallow pond and pumping water somewhere else?

Build a series of 1/3 meter deep swales throughout your property vs one big pond/deep well at the very bottom of your property to water your food forest.

If you just want fish check out GARDENPOOL

Hi Edgar,

What is this area used for? Orchard, firewood coppice, wild area? As Bengi suggests, swales would be good for a variety of options...

Is it possible to catch the water in swales, and move it along contour to a place where the topography and/or soil is better suited for storing it?

Your idea of a smaller pond, presumably fed by swales, that you use to feed a larger pond elsewhere, is reasonable... but does depend on the pump, the power source for the pump. Ease of this option will of course depend on how far you need to pump the water, and the reliability of the infrastructure.

I recall that Sepp Holzer uses a pump that relies on flowing water to move a small fraction (10%?) of that water uphill... how much water do you have moving through, and how much do you want to catch?

Thanks for replying. The area just below will be left wild, as it is mostly an outcrop with native trees between the rocks and is near the edge of the property. All the production areas are on higher ground, about 5m above. The water only flows during storms, nothing permanent. It causes some erosion though, but I'm working on it. I would like to catch as much water as possible, evaporation is about twice as much as rainfall.

Subsoil water storage higher in the property makes sense. You want to aim to get the water infiltrating higher in the property. A series of smaller on-contour swales as suggested would probably be your best bet. Water that infiltrates higher in the property will move downslope through the soil slowly over time allowing the roots of your plants to access it and protecting it from evaporation. I'd start swaling from the top and work down. When you are done there should be little direct run off reaching that bottom area as it will mostly have infiltrated already.

The whole property has on-contour swales and all the rain that falls on it gets infiltrated. What I'm trying to harvest is run off from outside the property that enters through the lower portion of it. A swale wouldn't help me much as it would be below everything else in the property. I intended to pond the water for wildlife use and irrigation during dry season.

Ah... draining from outside your property. That is a different beast.

What are the neighbours like? Could you divert the water higher up on their catchments and direct it across contours to higher up on your own site? Or perhaps get them invested in the idea of contour swales as well and improve the surrounding catchment too? Better infiltration in your neighbours land will help the overall water system in your area, with knock on benefits for your land too if you are down slope of them.

Rather than a drainage problem you could switch it for improved groundwater flows for a more prolonged period of the year.

Instead of going for a wildlife pond, create a tiny 1 meter deep pond.
Channel the runoff into the pond, and pump the water up to a higher elevation on your property.

Sadly this does require running water pipe/hose and getting a submersible pump and electricity (solar/battery).

The good news is that the water will be stored in the soil vs on the surface where evaporation is twice rainfall.