Planning permission - high water level

newhouse123

Any help appreciated!! Looking to build a house on my husband's land and we have recently had our trial holes dug and percolation tests completed. There is water at the bottom of the large trial hole. My engineer said that the council won’t be happy with the water in the hole after such a prolonged dry spell. Water table seems to be sitting at about 1.70m BGL. Is there anything we can do with this? Surely our engineer could suggest a waste treatment system suitable for this site in our planning application or is this a definite no go? Looking for any advice from anyone who may have been in a similar situation with their water table and got around it. Septic tank system for my husband's home house is also to the right of our site and there has never been any issues with that septic tank overflowing or seeping out etc..

Furze99

You need very site specific advice and not enough of that in OP above I'd be thinking. Essentially the idea of these regulations is to prevent any outflows from your septic tank or treatment system from polluting either your own water supply, neighbours supply or local watercourses etc. So if you had the right size & slope of site and a large percolation area draining well away from any issues - that might work and perhaps how your in laws system works. But maybe these factors don't work in your favour, hence engineers caution??

Calahonda52

2021_Septic tanks CodeofPractice_Web.pdf

You need to read this: in terms of design, the engineer has to work with what he is faced with.

There are a wide variety of different solutions, the more complex ones require frequent certified monitoring

re the existing ST, how do you know it hasn't seeped out?

The issue with proximity to high water tables etc has to do with will the aerobic digestion be complete before the outflow hits the water table/ steam/lake/watever.

sydthebeat

https://www.boards.ie/discussion/2058301177/planning-permission-high-water-level

did your engineer mention the "mottling" level as it is much more relevant than what the water level in the large hole in the middle of june.??

water at 1.7m below ground level in june doesn't really mean anything at all.

sprucemoose

https://www.boards.ie/discussion/2058301177/planning-permission-high-water-level

as suggested in the first response, its a bit hard to advise since it is a fairly site-specific issue. having said that, your engineer should be able to come up with an acceptable solution, its just that it may not be acceptable to you from a financial point of view unfortunately

FJMC

If the actual water table is at determined at 1.7m you should be able to find an acceptable solution.

However, if you only started hitting water at 1.7m in the summer the actual water table is likely to be higher - as mentioned above you may notice mottling higher up the sides of your excavation - and that mottling or water seepage into the excavation may give you a true indication of the water table level.

There still may be solutions even if you have a high water table but your full site assessment should determine what that solution is.

F