Retention/Detention Ponds in Florida
Retention/Detention Ponds in Florida
(OP)
I am trying to help a friend of mine with a site and a drainage plan. I've done some very small single family retention designs in the past but this one is a bit larger. My ESH is fairly shallow which would give me a large pond area if I design it to where it accepts all the runoff and make sure it recovers in 72hrs. The other alternative I believe is to design a detention pond and outflow a portion of the runoff to the swale (In the R.O.W) in the front of the property but I am not sure if this is allowed. Even if I did design it to take all the volume and treat it I believe I would still need to have a way for the water to get to the front swale in case it overflows.
The site is still relatively small at about 0.5 acre but I am trying to come up with the best design possible for this. Any feedback on possible solutions would be greatly appreciated
The site is still relatively small at about 0.5 acre but I am trying to come up with the best design possible for this. Any feedback on possible solutions would be greatly appreciated





RE: Retention/Detention Ponds in Florida
You'll need to check with the municipality to determine their design criteria. You'll also have to submit to one of the water management districts for approval. There are water management districts that cover the entire state, with each having its own area of responsibility. They do not have the same rules or review criteria, so be aware that you'll need to contact them as well before you do your design.
Some municipalities require both retention and detention facilities, even for a small site. Usually they require automatic splitting between the ponds. For the detention facility, you can usually pop off to either the Florida DOT's master facility for the roadway area or to the municipality's system. You'll obviously have to get permission. Depending on the municipality's requirements you will likely be required to attenuate pre- and post development runoff and prove the stage/storage conditions. Not difficult, just another hoop to jump through.
Good luck.
RE: Retention/Detention Ponds in Florida
Yes, I read through the water districts BPM and city requirements and this site falls under the exemption for permitting through the district. I still have to permit it through the city but they have less strict requirements and a little more flexibility with design. I am allowed to use a 5-year storm with a 20-min Tc. but if I design it as full retention they will require a DRI field test for infiltration. I can make it work either way but I am scratching my head on the best way to convey the runoff from the parking area in the front to the pond in the back of the property. I was thinking swales or small pipes running down the sides of the property to the pond in the back but I am not sure what is more practically accepted for construction and cost....
RE: Retention/Detention Ponds in Florida
RE: Retention/Detention Ponds in Florida
RE: Retention/Detention Ponds in Florida
Yes, the civil engineers try to construct dry retention ponds on all sites in the panhandle of Florida. Retention ponds directly infiltrate the stormwater into the shallow unconfined aquifer. When clayey soils are present at the surface, we will recommend a vertical sand chimney to key into deeper sand layers. Sand chimney construction observations are very important to verify the contractor is keying into the correct layer and to verify subsurface conditions are similar to the geotechnical borings.
RE: Retention/Detention Ponds in Florida
RE: Retention/Detention Ponds in Florida
Most of our sinkhole activity is centered along an area known as the Florida Ridge. It is an area extending from just south of the Florida-Georgia border to south central Florida, north and west of Lake Okeechobee. This area has limestone (some of which is dolomitic) that extends to the surface in many areas.
RE: Retention/Detention Ponds in Florida
RE: Retention/Detention Ponds in Florida
RE: Retention/Detention Ponds in Florida
RE: Retention/Detention Ponds in Florida