There is no specific containment method that must be used for wastewater collection/diversion. However, the system must be adequately designed so that the wastewater does not flow into storm drain inlet.
All mobile and existing businesses should use 1 of the following methods:
Portable containment areas can be made from waterproof tarps, heavy-duty plastic, or rubber matting equipped with berms to prevent wastewater from running into storm drain inlets or off-site. Materials that can be used for berms include sand bags or water-filled tubing. Whatever containment material is used, it must seal tightly to the ground so that no wastewater can pass under or over the berms.
When power washing smaller pieces of equipment, containment devices to use may include portable vinyl swimming pools, plastic 55-gallon drums on casters, and flat metal or plastic containment pads.
Depending on the volume of wastewater generated, it may be necessary to use wet-dry vacuum or a sump pump to discharge the wastewater to the landscaping or sewer.
Stationary or more permanent containment areas can be constructed with cement. Berms and pump systems may be used to contain wastewater and divert it to a holding tank.
Commercial wastewater collection systems are also available for power washing. These systems can range from portable wash pits to self-contained water recycling systems. A list of companies selling this type of equipment can usually be found in the telephone book under “Pressure Washing Services and Equipment."
Storm drain inlet covers can be made of an impermeable barrier such as a heavy-duty vinyl or plastic secured in place with materials such as concrete blocks, gravel bags, or sand bags. Storm drain inlet covers may also be available though commercial vendors.
Blocking storm drain catch basin inlets in the public right-of-way is prohibited unless permitted through an encroachment permit. Wastewater should be contained on-site.