Stormwater treatment apparatus

A stormwater treatment apparatus, comprising:

• a concrete vault having an inlet section, an outlet section and at least one midsection, said inlet section having a top wall, a bottom wall, a left side wall and a right side wall and an inlet end wall, said outlet section having a top wall, a bottom wall, a left side wall and a right side wall and an outlet end wall, said at least one midsection having a top wall, a bottom wall, a left side wall and a right side wall;
• an inlet located in said inlet section, spaced above said bottom wall of said inlet section;
• an outlet located in said outlet section spaced above said bottom wall of said outlet section, said outlet defining a permanent pool water surface elevation level;
• a first baffle positioned in front of said inlet in said inlet section, said first baffle extending from above said permanent pool water surface elevation level to below said permanent pool water surface elevation level, but being spaced above said bottom wall of said inlet section;
• a second baffle between said first baffle and said outlet having an upstream side and a downstream side, said second baffle connected to said bottom wall of said inlet section and extending upward no higher than said permanent pool water surface elevation level, said upstream side of said second baffle including at least a portion angled upward from said bottom wall of said inlet section and toward said outlet;
• a third baffle between said second baffle and said outlet having an upstream side and a downstream side, said third baffle connected to said bottom wall of said at least one midsection and extending upward no higher than said permanent pool water surface elevation level, said upstream side of said third baffle including at least a portion angled upward from said bottom wall of said midsection and toward said outlet;
• and
• a fourth baffle between said third baffle and said outlet, said fourth baffle extending from above said permanent pool water surface elevation level to below said permanent pool water surface elevation level, but being spaced from said bottom wall of said outlet section.

An apparatus for separation of pollutants in runoff that are less and more dense than the runoff water, comprising:

• a receptacle adapted to receive stormwater runoff flowing from all surface areas tributary to it, the receptacle having a bottom and a top, a left side-wall and right side-wall, and a front side-wall and end side-wall, forming a rectangular tank;
• an inlet for introducing stormwater flowing from tributary surface areas into the receptacle and an outlet for discharging water;
• at least four baffles positioned within the receptacle between the inlet and the outlet, with all of the baffles attached to both sides of the receptacle, with at least to baffles attached to the bottom of the receptacle and not attached to the top, at least one baffle attached to the top of the receptacle and not attached to the bottom, and at least one baffle that is not attached to the bottom and top of the receptacle;
• an inlet section for receiving water, for decreasing energy of the flowing water, and for uniformly distributing water across the width of the receptacle;
• one or more midsections for trapping materials more dense than water that settle out of water by gravity and for trapping materials less dense than water that rise to the surface of water by gravitational separation;
• an outlet section for discharging water at a controlled rate and for excluding materials more and less dense than water being discharged;
• where the outlet section includes an opening located on the end side-wall that allows water in the apparatus to discharge,
• where mesh screening from the bottom to the top of the apparatus is attached in a removable fashion to the end side-wall to form a half cylinder through which any water that discharges through the opening must pass prior to discharge.

An apparatus for separation of pollutants in runoff that are less and more dense than the runoff water, comprising:

• a receptacle adapted to receive stormwater runoff flowing from all surface areas tributary to it, the receptacle having a bottom and a top, a left side-wall and right side-wall, and a front side-wall and end side-wall, forming a rectangular tank;
• an inlet for introducing stormwater flowing from tributary surface areas into the receptacle and an outlet for discharging water;
• at least four baffles positioned within the receptacle between the inlet and the outlet, with all of the baffles attached to both sides of the receptacle, with at least two baffles attached to the bottom of the receptacle and not attached to the top, at least one baffle attached to the top of the receptacle and not attached to the bottom, and at least one baffle that is not attached to the bottom and top of the receptacle;
• an inlet section for receiving water, for decreasing energy of the flowing water, and for uniformly distributing water across the width of the receptacle;
• one or more midsections for trapping materials more dense than water that settle out of water by gravity and for trapping materials less dense than water that rise to the surface of water by gravitational separation;
• an outlet section for discharging water at a controlled rate and for excluding materials more and less dense than water being discharged;
• where the water surface level in the apparatus is controlled by the outflow opening invert elevation;
• where the opening is an aperture machined into a cap that is sized to fit exactly around the circumference of an outflow pipe that protrudes a short distance into the outlet section;
• where access to the inlet section, the outlet section, and all midsections is provided by manholes that are of sufficient size to allow cleaning of the vault via pump out or another vacuum removal process;
• where a short, hollow cylinder of a diameter equivalent to the diameter of the manhole opening extends down from the top of the apparatus for several inches into the apparatus for all manholes associated with midsections.