Storm water reservoir with low drag

A multi-layer gallery having an elongated arched body and first and second ends, the gallery forming an elongated arched interior space with an open bottom for liquid to flow therethrough, the multi-layer gallery comprising:

• a first exterior layer running transversely to the length of the elongated arched body forming a plurality of spaced apart upstanding ribs;
• a second interior layer forming a surface which is sufficiently smooth to reduce frictional drag of liquids flowing in the gallery;
• said first exterior layer extending from the first end of the elongated section to the second end of the elongated section;
• and
• said second interior layer extending from the first end of the elongated section and terminating prior to the second end of the elongated section to form a connecting mechanism;
• said connecting mechanism comprising a starting rib located at the first end of the gallery, and an end rib located at the second end of the gallery, wherein a first and a second gallery may be connected together by overlapping a starting rib of the first gallery over an end rib of the second gallery, said starting rib being larger than the end rib, and the second interior layer extending from the second end of the gallery and terminating prior to the first end of the gallery at the last upstanding rib of the first exterior layer.

A method for providing a multi-layer gallery with an elongated arched body having first and second ends and having a reduced coefficient of friction for an interior space with an open bottom to facilitate the flow of liquid and particles therethrough, including the steps of:

• providing a first exterior layer, the first exterior layer forming a plurality of upstanding ribs spaces apart along the elongated arched body and running transversely to the length of the elongated arched body;
• providing a second interior layer, the second interior layer forming a smooth continuous surface;
• adhering the first exterior layer to the second interior layer to form a single multi-layer gallery;
• extending the first exterior layer from the first end of the elongated section to the second end of the elongated section;
• and
• extending the second interior layer from the first end of the elongated section and terminating prior to the second end of the elongated section at the last upstanding rib of the first exterior layer to form locking mechanisms.

A plastic gallery for containing and distributing liquid in a leaching or drain field, said gallery comprising:

• an elongate arched body having first and second ends and an open bottom, said arched elongate body being formed of a corrugated layer and an inner plastic layer, said corrugated layer being a corrugated plastic having a plurality of ribs extending along a substantial length of said elongate body, said inner plastic layer being affixed to an inner surface of said corrugated layer and having a substantially smooth inner surface extending along a substantial length of said elongate arched body, said substantially smooth inner surface having a low frictional drag with respect to liquid flow;
• said corrugated layer extending from the first end of the elongated to the second end of the elongated section;
• and
• said inner plastic layer extending from the first end of the elongated section and terminating prior to the second end of the elongated section at the last upstanding rib of the corrugated layer, to form a connecting mechanism associated with said first and second ends for connecting said gallery with another gallery.