Plastic detention chamber for stormwater runoff and related system and methods

A plastic, corrugated open bottom chamber includes features such as one or more of (i) sub-corrugation features on corrugation crests and/or corrugation valleys, (ii) stiffening fingers on the bottom of chamber foot portions, (iii) a viewport configuration that intersects only a single corrugation crest and (iv) a unitary end wall. A method of producing chambers with or without a unitary end wall using a common mold tool is also provided. A method of interconnecting chambers to form a chamber rows is also provided.