(A) Dams are classified as to their size and their hazard/damage potential in the event of failure.
(B) The construction or major modification of all Class I (high hazard) and Class II (moderate hazard) dams require an IDNR/OWR dam safety permit.
(C) Some Class III (low hazard) dams require an IDNR/OWR dam safety permit, depending on the drainage area to the dam, the height of the dam and the impounding capacity behind the dam. Most off-channel detention basins that have an embankment are non-jurisdictional Class III dam. It is not required that IDNR/OWR sign off on all non-jurisdictional Class III dams.
(D) A consulting engineer with dam safety knowledge can estimate a hazard classification and determine if an IDNR/OWR dam safety permit is required.
(E) A permit application submittal must be made to IDNR/OWR for the construction or major modification of jurisdictional dams.
(F) Regulated dams may include weirs, restrictive culverts or impoundment structures.
(Prior Code, § 157.022) (Ord. 08-023, passed 7-22-2008)