1. In order to comply with the City of Paris’s permanent stormwater standards for new development and redevelopment projects, design and install SCMs as established by Tennessee Department of Environment and Conservation Rule 0400-40-10-.04 and comply with other requirements of Rule 0400-40-10-.04. For design purposes, total suspended solids (TSS) may be used as the indicator for the reduction of pollutants.
2. SCMs must be designed to provide full treatment capacity within 72 hours following the end of the preceding rain event for the life of the new development or redevelopment project. The designer may select from the most appropriate alternatives listed in the City of Paris’s BMP Manual.
3. Designs shall be based on the 24-hour design storm adopted by the City of Paris. The City of Paris has adopted, for use in designing water quality SCMs, the design storm requirements as established in Tennessee Department of Environment and Conservation Rule 0400-40-10-.04. The Post Construction/Permanent water quality design storm is a 1-year, 24-hour storm event for water quality SCMs. See definition of Design Storm Event for the municipality’s rainfall amounts for each return period interval. See NOAA Atlas 14 for precipitation amounts: https://hdsc.nws.noaa.gov/pfds/pfds_map_cont.html?bkmrk=tn.
4. Water Quality Riparian Buffers . Post Construction/Permanent water quality riparian buffers shall be those buffers defined in 13-502 above and shall meet the requirements described in this ordinance. The criteria for the width of the post construction/permanent buffer zone can be established on an average width basis at a project, as long as the minimum width of the buffer zone is more than the required minimum width at any measured location. If the new development or redevelopment site encompasses both sides of a stream, buffer averaging can be applied to both sides, but must be applied independently. Water quality riparian buffer widths are measured from the top of bank also referred to as the “ordinary high-water mark.” Stormwater discharges should enter the post construction/permanent water quality riparian buffer as sheet flow, not as concentrated flow, where site conditions allow.
Post Construction/Permanent buffers for waters with available parameters for siltation or habitat alteration or unassessed waters:
a. Average buffer width: 30 feet.
b. Minimum buffer width: 15 feet
Post Construction/Permanent buffers for Exceptional Tennessee Waters or waters with unavailable parameters for siltation or habitat alteration:
a. Average buffer width: 60 feet.
b. Minimum buffer width: 30 feet
The designer/operator must comply with the vegetation requirements and the permissible land uses set forth for buffers in the MS4 permit.
(Ord. #1307, 09/05/24)