(A) In calculating the total area of land disturbance, for the purposes of determining applicability of this subchapter to the project, the following guidelines should be used:
(1) Off-site construction activities that provide services (for example, road extensions, sewer, water, and other utilities) to a land disturbing project site, must be considered as a part of the total land disturbance calculation for the project site, when the activity is under the control of the project site owner.
(2) Strip developments will be considered as one project site and must comply with this subchapter unless the total combined disturbance on all individual lots is less than one acre and is not part of a larger common plan of development or sale.
(3) To determine if multi-lot project sites are regulated by this rule, the area of land disturbance shall be calculated by adding the total area of land disturbance for improvements, such as, roads, utilities, or common areas, and the expected total disturbance on each individual lot, as determined by the following:
(a) For a single-family residential project site where the lots are one-half acre or more, one-half acre of land disturbance must be used as the expected lot disturbance.
(b) For a single-family residential project site where the lots are less than one half acre in size, the total lot must be calculated as being disturbed.
(c) To calculate lot disturbance on all other types of projects sites, such as industrial and commercial project sites, a minimum of one acre of land disturbance must be used as the expected lot disturbance, unless the lots are less than one acre in size, in which case the total lot must be calculated as being disturbed.
(B) The calculation methods as well as the type, sizing, and placement of all stormwater pollution prevention measures for construction sites shall meet the design criteria, standards, and specifications outlined in the “Indiana Stormwater Quality Manual” or the Stormwater Technical Standards Manual. The methods and procedures included in these two references are in keeping with the above stated policy and meet the requirements of IDEM’s Rule 5.
(Ord. 2020-1E, passed 1-6-20)