A prerotation basin for use in a sump pit or wet well includes a basin body having an upstanding exterior wall, an interior concavity for placement of a pump inlet therein, and a fluid entry channel formed in the basin body defined by a discontinuity in the upstanding exterior wall, where the fluid entry channel has a channel floor, the threshold of which is at an elevation that is equal to or lower than the elevation of the bottom surface of the interior concavity. The prerotation basin thereby provides a channel floor that slopes upwardly toward the bottom surface of the interior concavity to provide better solids entrainment in fluid being processed from the sump pit or wet well, and to provide self-flushing of the basin.

A stormwater vault and a process for servicing the stormwater vault speeds the process of cleaning a stormwater vault. The stormwater vault has a built in liquefaction system for liquefying settled debris in the vault which works together with a sloped or angled floor in the vault. The settled debris is flushed toward the inlet to a vacuum removal line inserted into the vault through an access opening for removing the settled debris from the vault.

Stormwater management systems, methods, and apparatuses for containing and filtering runoff may be provided. In one implementation, a flared end ramp for managing flow of material into a stormwater chamber may be provided. The flared end ramp may include an inlet end configured for connection with a pipe, a side wall of the flared end ramp having a rounded profile at the inlet end; an outlet end configured for placement within the stormwater chamber; and an inclined surface extending between the inlet end and the outlet end of the flared end ramp and configured to deliver material from the pipe into the stormwater chamber. The outlet end of the flared end ramp may have a larger width than the inlet end of the flared end ramp such that the inclined surface is angled laterally outward from the inlet end toward the outlet end.

A flow control assembly comprising: a mounting bracket attachable to a wall of a collection chamber, the mounting bracket having an opening extending therethrough; a flow control module detachably coupled to the mounting bracket, the flow control module having an inlet and an outlet, the outlet being aligned with the opening of the mounting bracket; and a gasket having an opening extending therethrough, the opening being smaller than the outlet of the flow control module and the opening of the mounting bracket. The gasket is disposed between the flow control module and the mounting bracket so as to seal the flow control module against the mounting bracket, with the opening of the gasket aligned with the outlet of the flow control module and the opening of the mounting bracket so as to restrict flow out of the flow control module. Also described is a corresponding kit of parts and method of installation.

A method of controlling vapor emissions using a liquid vapor trap containing an effective amount of a barrier fluid that will greatly reduce the volume of noxious and/or other gases emitted from a containment (natural or man-made) into the atmosphere. Examples of containment include, but are not limited to septic, fossil fuels and landfills.

Stormwater management systems, methods, and apparatuses for containing and filtering runoff may be provided. In one implementation, a flared end ramp for managing flow of material into a stormwater chamber may be provided. The flared end ramp may include an inlet end configured for connection with a pipe, a side wall of the flared end ramp having a rounded profile at the inlet end; an outlet end configured for placement within the stormwater chamber; and an inclined surface extending between the inlet end and the outlet end of the flared end ramp and configured to deliver material from the pipe into the stormwater chamber. The outlet end of the flared end ramp may have a larger width than the inlet end of the flared end ramp such that the inclined surface is angled laterally outward from the inlet end toward the outlet end.

A flow control assembly comprising: a mounting bracket attachable to a wall of a collection chamber, the mounting bracket having an opening extending therethrough; a flow control module detachably coupled to the mounting bracket, the flow control module having an inlet and an outlet, the outlet being aligned with the opening of the mounting bracket; and a gasket having an opening extending therethrough, the opening being smaller than the outlet of the flow control module and the opening of the mounting bracket. The gasket is disposed between the flow control module and the mounting bracket so as to seal the flow control module against the mounting bracket, with the opening of the gasket aligned with the outlet of the flow control module and the opening of the mounting bracket so as to restrict flow out of the flow control module. Also described is a corresponding kit of parts and method of installation.

A stormwater vault and a process for servicing the stormwater vault speeds the process of cleaning a stormwater vault. The stormwater vault has a built in liquefaction system for liquefying settled debris in the vault which works together with a sloped or angled floor in the vault. The settled debris is flushed toward the inlet to a vacuum removal line inserted into the vault through an access opening for removing the settled debris from the vault.

A method of configuring a vortex flow control device 2 comprising a vortex chamber 4, an inlet 6 and an outlet 8 arranged at one end of the vortex chamber 4, wherein the method comprises the steps of: setting a target maximum flow rate F.sub.T-MAX through the outlet 8 for a predetermined pressure P.sub.T-MAX at the inlet; setting a target vortex initiation flow rate F.sub.T-VI through the outlet 8 at which vortex flow within the vortex chamber 4 initiates; determining the actual maximum flow rate F.sub.A-MAX through the outlet 8 for the predetermined pressure P.sub.T-MAX at the inlet 6; determining the actual vortex initiation flow rate F.sub.A-VI through the outlet 8; determining an error parameter E based on at least one of the actual maximum flow rate F.sub.A-MAX and the actual vortex initiation flow rate F.sub.A-VI and at least one of the target maximum flow rate F.sub.T-MAX and the target vortex initiation flow rate F.sub.T-VI; comparing the error parameter E against a target condition C.sub.T; and, if the error parameter E fails to satisfy the target condition C.sub.T, modifying at least one characteristic of the vortex flow control device 2 so as to vary at least one of the actual maximum flow rate F.sub.A-MAX and the actual vortex initiation flow rate F.sub.A-VI so that the modified vortex flow control configuration produces a hydraulic response that more closely satisfies the target condition C.sub.T.

A drainage device is provided. The device includes a novel floating surface drain or skimmer to manage draining of liquid, such as draining of water from stormwater impoundment ponds or structures.