Chapter 4 Flashcards
What are the purposes of inspection and testing?
Identifying existing and potential problems
Evaluating detected problems
Determining location of problems
Providing information about problems
What are the types of collection system problems
Design related Improper installation Inadequate ordinances Improper inspection Changing populations Disaster
Define water table
The upper surface of the zone of saturation of groundwater in an unconfined acquifer.
Define surcharge
Sewers are surcharges when the supply of water to be carried is greater than the capacity of the pipes to carry the flow.
Define infiltration
Water entering the collection system through deteriorated or broken pipes or joints.
Define inflow.
Water that is not polluted and should uh led be in a stormwater drainage system.
Define S.S.O.
Sanitary Sewer Overflow.
Define ponding
Surface water that accumulates at manholes.
Define exfiltration.
Leakage of wastewater out of the collection system through broken or damaged pipes and manholes.
What are sources of I / I?
Illicit connections to the public sewer. Downspouts, basement dumps foundation drains, breaks on pipes, open joints.
Define lateral connection
Typically a small diameter pipe that connects to the main line.
What is the number of operators required to enter a manhole?
3
What is the frequency of manhole inspections?
1- 5 years.
Define offset.
A pipe joint that has lost its bedding support causing one of the pipe sections to drop and the pipes no longer line up properly.
Define lamping.
Using a light or reflected sunlight to inspect a sewer between two adjacent manholes.
What are winches used for.
Pulls camera on demand and for specialized use when self propelled transporters are not.suitable.
What is the typical number of staff required for CCTV operation
2
3 if in traffic.
Which direction should the camera move
Direction of flow.
Define offset joints.
Horizontal offset is when the joint section has moved out of alignment.
Vertical offsets are drops or jumps on joints.
Define smoke tesfing.
testing. Non toxic smoke filled air down a manhole and sewer pipe and wait for visible smoke.
Define cured in place pipe.
Trenchless pipe rehabilitation that lines existing pipe.
Define dye testing.
Simple cost effective way to determine if sewer facilities are connected to wastewater collection system.
What is the recommended manhole inspection schedule.
1-5 years.
