Exfiltration apparatus

An exfiltration apparatus for removing contaminants from surface runoff water, the apparatus comprising:

• a housing defining a downward fluid flow path extending from a fluid inlet disposed on a top side of the housing to a fluid outlet disposed on a bottom side of the housing;
• a filter portion positioned within the housing;
• a particulate collecting plate disposed within the housing in a horizontal orientation between the fluid inlet and the filter portion, the particulate collecting plate including a recessed particulate collecting lower portion adjacent to the filter portion and a raised upper portion adjacent to the fluid inlet and defining a plurality of apertures, and
• wherein the housing comprises a first portion defining the fluid inlet and a second portion defining the fluid outlet, the first housing portion being removable from the second housing portion to access the filter portion;
• and
• wherein surface runoff water flowing along the downward fluid flow path passes through the particulate collecting plate and through the filter portion before exiting through the fluid outlet.

A method for removing contaminants from surface runoff water from an upper surface of a ground substrate, the method comprising:

• installing an exfiltration apparatus in the ground substrate, the exfiltration apparatus comprising:
• a housing defining a downward fluid flow path extending from an upper fluid inlet disposed in an upper portion of the housing to a lower fluid outlet disposed in a lower portion of the housing, the fluid inlet being exposed to receive surface runoff water from the upper surface of the ground substrate, the fluid outlet being connected with a drainage system;
• and
• a filter portion positioned within the housing;
• with the upper portion of the housing removed from the lower portion of the housing, inserting a particulate collecting plate within the housing in a horizontal orientation above the filter portion, such that a recessed particulate collecting lower portion of the particulate collecting plate is adjacent to the filter portion;
• assembling the upper portion of the housing with the lower portion of the housing, such that a raised upper portion of the particulate collecting plate defining a plurality of apertures is adjacent to the fluid inlet, and
• allowing surface runoff water entering the fluid inlet to flow along the downward fluid flow path, passing through the particulate collecting plate and through the filter portion before exiting through the fluid outlet, wherein contaminants carried by the surface runoff water are collected in the recessed particulate collecting lower portion of the particulate collecting plate.