Why is red clay a problem for porta potties?
Upstate red clay holds water and swells when wet, then shrinks and cracks when dry. Spartanburg averages about 50 inches of rain a year, so the ground under a unit changes often. A porta potty on bare clay can sink on 1 corner and lean after a hard rain.
Most of the Piedmont sits on deep, red, clayey soils like the Cecil and Appling series, which the SC DNR soils guide lists with high shrink-swell potential. Rain totals come from the SC State Climatology Office, which lists 50.24 inches a year for Spartanburg County.
Should a porta potty sit on plywood or gravel?
Both work. A full 4-by-8-foot sheet of exterior plywood or a pad of crushed stone gives a porta potty a firm, level base on clay. A standard unit is about 44 by 47 inches, so 1 plywood sheet covers the footprint with room to step out the door.
| Base | Works on clay? | Notes |
|---|---|---|
| Concrete or asphalt | Best | Already level and firm; check the slope |
| Packed gravel pad | Very good | Drains fast; rake flat before delivery |
| Plywood sheet | Good | Quick fix for lawns and soft spots |
| Dry, short lawn | Fair | Fine in dry weeks; watch it after storms |
| Bare, wet clay | Poor | Sinks and leans; add plywood or gravel first |
Lay the base before delivery so the unit sits flat from day 1. Set the base a little higher than the ground around it so rain runs away.
Will the service truck rut my yard?
A loaded service truck is heavy, and wet clay ruts under its tires. The truck's hose reaches about 30 feet, so set the unit within 30 feet of a driveway, street or gravel lane. Then the truck stays on hard ground for delivery, every service visit and pickup.
On a new home site, place the unit by the construction entrance or the gravel drive. Job site units get weekly visits, so a muddy path gets worse each week. See the construction porta potty rental page for job site setup.
Our placement checklist covers gates, wires and septic fields too.
How do I keep a porta potty from tipping in a storm?
A porta potty tips when wind catches the tall shell on soft ground. A standard unit stands about 90 inches tall and is lightest when the tank is near empty. Set the unit on a firm base, out of open wind lines, and ask dispatch about staking the unit when storms are coming.
Tuck the unit beside a building, a fence or a row of parked equipment. Face the back of the unit toward the open field. Never tie a unit to a tree or a power pole.
What should I do if a porta potty starts to lean?
A leaning porta potty should not be used until the unit is set level again. Call dispatch at (864) 209-8751, Monday to Saturday, 7 AM to 7 PM. Do not shove the unit upright, because the tank may hold up to 60 gallons of waste that can slosh and spill.
Job site units are checked for level at every weekly service visit. After a big storm, walk the site, look at each unit and call if a door will not latch.
What happens to an event rental if it rains?
Rain does not end the rental for a weekend event. Units drop on Friday and pick up on Monday for the same price as 1 event day, so a Sunday rain date is covered. Set the unit on high, firm ground the day before, away from low spots where water pools.
Plan the walking path too. A strip of plywood or a gravel path to the door keeps shoes out of the mud. See event porta potty rental for how weekend drops work, or the full rental process.