Search results
Results from the WOW.Com Content Network
The pit sat full of water for much of that time. We're moving the new house farther back on the lot - about 20 feet. A recent soil boring has discovered a perched water table at 36 inches on a hard clay layer at 41 incehs. We believe the real water table to be no higher than 5 feet. I want to excavate to at least 4 feet for the new basement.
I also did a quick Google and it looked like perched water table requires an impenetrable layer. But presumably water can flow freely through a loose layer of rocks. Also the picture didn't make sense to me because it assumes the capacity of the soil is the same in both cases but in the right picture there's actually like 20% less soil so ...
Perched water tables A perched water table (or perched aquifer) is an aquifer that occurs above the regional water table. This occurs when there is an impermeable layer of rock or sediment or relatively impermeable layer above the main water table/aquifer but below the land surface. If a perched aquifer's flow intersects the surface, at a ...
Water moving downward through the unsaturated zone will be intercepted and accumulate on top of the lens before it moves laterally to the edge of the lens and seeps downward to the regional water table." Your surface water doesn’t fit the definition as perched as it isn’t an aquifer.
Adding gravel at the bottom prevents some soil from washing out but it increase the height at which water is held. This could rot your roots out. Instead, you should mix the soil amendments into your soil to increase the air pockets for drainage, thus, decreasing the perched water table.
Downward percolating water may be intercepted and a saturated zone of limited areal extent formed. this results in a perched aquifer with a perched water table [4]. An unsaturated zone is present between the bottom of the perching bed and the regional water table. A perched aquifer is a special case of an unconfined aquifer.
Although no free water was encountered in the test borings, the soil color patterns indicate a perched seasonal high-water table at approximately elevation 34.0 which is 2.6 feet above the basement floor elevation. This is an epiaquic condition which means the groundwater is "perched" above the firm clayey C horizon during the wet season.
If you use a sump pump, make sure to keep it pretty shallow. With your work at the geotech firm, you may be familiar with effective soil pressures in saturated soil. If you lower your water table below the normal/dry level then you could cause subsidence and affect your foundation.
The water seems to run right along the bedrock surface. Its a perched water table and when the borhole is dug and hits the rock it immediately fills up. When it rains it almost overflows out the top. Thanks for the hydraulics tip.
A soil scientist reports that the area where my septic field is located is Alcovy with indications of a perched water table at 30-50". The septic field has an average depth of 70", which would make the deepest point around 80".