Pondering in Scotland

Hi!
I have a field that floods like crazy by the front entrance in winter. In the Google maps screenshot I've drawn where the water gathers in dark blue and the arrows show downhill areas. Within the field (mine is the strip with buildings in it, the other fields pictured belong to my neighbours and are just grass) the slope is very slight, it is a relatively flat field. The road runs downhill from houses to the fields and the lay of the land where the field entrances are is lower than the road, and the flooding comes up to I think 6 inches below the road at its worst. I don't have control over what happens in my neighbours fields, so I am wanting to design a system that can just lessen the flooding. Upfield I have one small pond at the very top of my 2 acre strip and so far have one swale with shrubs and plan to have more. My idea for the entrance is to dig a sizeable pond just touching the edge of the flood zone with a pipe that would drain off water from the entrance into the pond. And I'm thinking I'd need a second pond slightly over and further removed from the flood zone to catch overflow, probably via a pipe or possibly a grassy spillway. The subsoil is excellent clay and even my small 2 ft deep pond upfield retains water nicely. The issues are: 1. the amount of water will be more than my ponds can handle and so are ponds not a great idea? And 2. that the hedge line is a few feet below the road, making that area a natural water sink. Looking for opinions, ideas, etc. Thank you

Hi Syd, Welcome to Permies! Thanks for your detailed post....
Just a few thoughts - so you're  looking to try and reduce the flooding at the entrance to your field? I'm not sure a pond will necessarily help with this. What is your sub soil like (edit, sorry you did say clay)? Water tends to find a level until it seeps away or evaporates, so if the water has nowhere to go, then I think it will still reach the same level. You might get a residual seasonal pond for a bit longer.
Is there any 'downhill' for the water to go to that you could clear drains to? or is this area a local low spot with no way out?

Nancy Reading wrote:Hi Syd, Welcome to Permies! Thanks for your detailed post....
Just a few thoughts - so you're  looking to try and reduce the flooding at the entrance to your field? I'm not sure a pond will necessarily help with this. What is your sub soil like (edit, sorry you did say clay)? Water tends to find a level until it seeps away or evaporates, so if the water has nowhere to go, then I think it will still reach the same level. You might get a residual seasonal pond for a bit longer.
Is there any 'downhill' for the water to go to that you could clear drains to? or is this area a local low spot with no way out?

Hi Nancy and thanks for your reply! Not sure if this is how I reply on this site, but I didn't see a reply button. I was thinking the area of soil I remove to dig the pond would be where water would go, but I think I understand what you're saying. The only option to drain the water completely away is to have a pipe laid underneath the road to the burn that runs parallel on the other side of the road. I did get a quote to do this and it's well out of budget unfortunately, and for me not a DIY job. I got waders, so I can cope, though hoping for a better solution

This is another idea I've had since posting. A deep and wide trench with berm (not on contour) running parallel to the hedge on the inside of the field, berm planted with willow and trench with typha, with a trickle pipe leading to one pond, and then a level sill spillway leading to a second pond

Ponder this. What if you dug a deep pond purposefully below the bottom of the clay level? Line the sides of pond with the clay. It would catch the water but not hold it.  It would be like a bucket with a sieve as a bottom. Water would gravity feed your aquifer.  

Just a though I have no idea what your local geology is like.

One thing is that the soil that you remove when digging the pond may make enough spoil to make a causeway above the level of the water :)
It sounds like you have lots of possibilities there. Do you have access to digging equipment? If you do dig the pond(s) you will want to make sure that the top soil stays on top and the clay goes underneath. It's a lot of work but ponds can have so many functions....Is there an opportunity to create a reflected light microclimate at all for a favoured growing area? Crops that grow in boggy areas? Fish or other water loving creatures? Seasonal ponds are valuable habitats, but  if you can extend the season you get more options.

Jeff, thank you for the idea! I'm not sure if the geology either, as the clay seems to go on and on. And I do want to hold water year round, but I will keep this idea in mind anyways.
Nancy thank you. I do plan on adding pond plants and hopefully fish if the water levels remain stable enough. I've started on the trench! I think that was a missing link for me, having an initial collection point to lead to a pond system. And the extra spoils from this I'm hoping to make a shower using earth plaster and tadelakt! Though it would be a good idea to use some to raise a little level

Permaculture was developed in Australia with dry climates in mind. I find its water management strategies are geared to holding on to water as long as possible with swales, and it really works but I find it does nt have alot to say when too much water is the issue not too little.  

I an in Australia and see water your issue as a great thing to have.
Some questions;
- is the flooding causing any problems?
- how long does it stay flooded for ?

John, it is a great problem to have! I farmed in Colorado before here and I prefer the wet to the dry. It can stay flooded for weeks at a time if we get rain continuously. It's also slower to drain in winter and frequently the ground in the field is saturated. For me it causes issues with access, and I'd also like to use some of the front of the field for grazing if possible. Also the front hedge seems to suffer a bit from the soaking

OK, so it sounds like the road works may have caused the build up.
A solution maybe to approach the local authority and discuss the matter, thy may volunteer to stop the 'flooding'
It will be a matter of law and they can they be held responsible for the flooding and consequent loss to yourself.

That could be something to investigate, though because it's a private road owned in part by myself and then by the other homeowners in the steading, I don't think I'll come up with much. It's been a dirt or rubble road for at least 200 years, the tarmac will have been sometimes since the 1990s