Periodic maintenance and inspections of the wastewater service connections of many different types of facilities are required. These maintenance and inspection activities are almost impossible without access through a manhole. If the manhole is on the city main at the point of connection for a particular facility's wastewater service line, it is simply referred to as a wastewater manhole. If the manhole is installed at or near the property line on property owner's side of the wastewater service line, it is referred to as a control manhole.
Any facility whose wastewater service line is not already connected at a wastewater manhole would be required to have a control manhole if:
The facility is or will be discharging wastewater regulated under Chapter 15-10 of the Austin City Code; or
The City can show through documented historical data or information that problems such as line stoppages, backups, overflows, corrosion, high grease or solids, etc. exist at the part of the collection system to be used by the facility; or
The facility has a water meter larger than two inches (2") in diameter, has a wastewater discharge line larger than four inches (4") in diameter, and/or has more than fifteen living or dwelling units.
For those facilities with multiple sewer taps, the requirement to have a control manhole would apply to each individual tap.
Periodic monitoring and inspection of the wastewater discharged from many types of facilities is required to determine compliance with applicable effluent limitations.
A sample port would be required for any facility discharging wastewater regulated under Chapter 15-5 of the Austin City Code. If the wastewater manhole or control manhole is located in an area accessible to sampling, then Pretreatment Program staff may decide to accept it as the sample port. This determination is conducted on a case-by-case basis. In those cases where an existing manhole is not acceptable as a sample port, the installation of a sanitary "tee" cleanout on the wastewater service lateral downstream of all plumbing connections is acceptable as a sample port. Again, the sample port must be installed in an area accessible to sampling and away from any vehicle traffic.