Season High Water Table - Florida
Season High Water Table - Florida
(OP)
Greeting all,
I need some help to identify the season high water table for a septic design I am working on.
What is the best way to get this information.
This is for a single family lot in naples Florida.
Thanks in advance for any help provided.
I need some help to identify the season high water table for a septic design I am working on.
What is the best way to get this information.
This is for a single family lot in naples Florida.
Thanks in advance for any help provided.





RE: Season High Water Table - Florida
RE: Season High Water Table - Florida
The regulating agency will probably require a geotechnical report stating the seasonal high water table, but some may accept the soil survey data.
Throughout Florida, except for the northwest, you will probably need to elevate your septic field above grade. The groundwater is usually too shallow to allow for an underground system.
RE: Season High Water Table - Florida
To get the high groundwater level for the area, you will either need an engineer to give that to you or also as jgailla notes, you might get by with the generalized soil data from the USDA. That will depend on what the health department in your county requires. Usually the building department or the health department in your county can give tell you what is acceptable for their application.
RE: Season High Water Table - Florida
Thanks.
RE: Season High Water Table - Florida
When you hire your geotech, make sure to specify that he needs to give you a SHWT determination, not just a determination of where the groundwater is currently. Groundwater elevations in FL fluctuate, and the high fluctuations leave staining in the core sample from organics floating on the top edge of the water. It's this stain depth that he needs to determine. He will give you the results in terms of depth, not elevation, so if you need to determine an elevation instead of just a depth you'll also need to have a surveyor shoot the pit locations.
If you're in a swampy area that is inundated during the wet season, an ecologist can give you a similar analysis by looking at vegetative indicators for how high it gets above the ground.
FL is a very unique place to do engineering in the states.
Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com
RE: Season High Water Table - Florida
http://maps.waterdata.usgs.gov/mapper/index.html
Look for a site screened in the surficial aquifer. There are a bunch in the Naples region. It would probably be best to find 3 or 4 that surround your property and take an average of those. Some basic statistical manipulation of the daily data, and adjustment for the site elevation may be needed.
RE: Season High Water Table - Florida
Thanks all for the help.
RE: Season High Water Table - Florida
Mike McCann, PE, SE (WA)
RE: Season High Water Table - Florida
Here is some quick information:
http://nesoil.com/images/redox.htm
http://nesoil.com/properties/eshwt.htm
RE: Season High Water Table - Florida
Where the existing elevation of the bottom surface of the drainfield is less than 24 inches above the wet season high
water table, the bottom of the drainfield shall be maintained at the existing separation or a minimum of 12 inches above the wet season high water table, whichever is greater.
Where the bottom of the drainfield is less than 12 inches above the wet season high water table, the drainfield shall be
brought into full compliance with all new system standards, as long as it is the intent of the applicant to proceed with the addition to the residence.