What are the design requirements for wet well, basin, tank or reservoir overflows?
• Overflows of wastewater must be contained and not allowed to spill onto the ground. If the overflow from a storage vessel is not connected to a sewer or the head works of the plant a suitable means of onsite containment must be included in the design. Typically, lined onsite emergency retention basins are used to contain an overflow. Counterweighted flapper valves or self-sealing valves which open and close automatically when an overflow occurs must be installed on the end of the overflow discharge pipe to control odors and prevent the ingress of birds and insects.
