(a) Concrete for bases and poured structures shall have a compressive strength of 3000 p.s.i. in 28 days, and a minimum of five sacks of cement per cubic yard. Slump shall not exceed four inches.
(b) Precast manholes shall have eccentric cone top.
(c) Manhole steps shall be required.
(d) Manhole frame and cover shall be the type known as "Detroit Standard" East Jordan Iron Works #1060 or approved equal with type A lids at low points. Type B lids may be used where surface water cannot enter. All frames shall have external chimney seals attached thereto. The bearing surface shall be machined to prevent rocking.
(Ord. 11-06. Passed 5-3-11.)