Chapter 1 - Existing Stormwater Quality Management Overview1.0 Initial Evaluation of Logansport's Stormwater Quality Management This chapter describes the City of Logansport's stormwater quality management efforts prior to the development and implementation of the proposed Stormwater Quality Management Plan (SWQMP) provided in the following chapters. The following subsections are summaries of the material presented in the City of Logansport's Part B submittal. 1.1 Current Stormwater Management The Logansport Stormwater Management Board was formed in 1992 and consists of three members. Logansport Municipal Utility acts as their technical resource, as do outside consultants. The Board uses a monthly user fee for stormwater. The fee is a function of the imperviousness of a given land use. Prior to the development of the Stormwater Quality Management Plan, the Logansport Stormwater Management Board did not have a Stormwater Quality Ordinance. 1.2 MS4 Area Boundary Narrative The MS4 Area boundary is defined as the City of Logansport's corporate limits. The MS4 Area Boundary Narrative Summary can be found in Appendix A . The mapped boundary of the MS4 area is shown on the MS4 Conditions Map , Appendix B . 1.3 Watersheds United States Geological Survey National Hydrogeological Database was used, and five primary watersheds were identified within the City's corporate limits. The 14 - digit hydrogeological unit codes (HUCs) and the names for the watersheds are: 1. No. 05120105010010: Wabash River - Grants Run 2. No. 05120104070070: Eel River - Horney Creek 3. No. 05120101180040: Wabash River - Biddle Island 4. No. 05120104070060: Eel River - Tick Creek 5. No. 05120101180020: Wabash River - Rock Island 1.4 Receiving Streams The following water bodies were identified in the Part B submittal as receiving streams. There have been no changes since that submittal. 1. Wabash River 2. Eel River 3. Horney Creek 4. Goose Creek 1.5 Outfalls There are no additional known stormwater outfalls to add since the Part B submittal. For reference, the stormwater outfalls are shown on the MS4 Conditions Map, Appendix B . 1.6 Estimate of the Linear Feet of MS4, Segregated by Conveyance Type The City of Logansport has estimated that there are approximately 35,900 linear feet (6.80 miles) of pipes and 2,200 linear feet (0.42 miles) of ditches. Therefore, the MS4 Conveyance system is approximately 7.22 miles in length. 1.7 Description of Current Structural and Nonstructural BMPs Logansport has one municipally owned and operated retention basin. The retention basin is located at the Logansport/Cass County Industrial Park. This retention basin is effective in slowing down the discharge rate from its watershed. Slowing down the discharge rate helps to prevent erosion from high water velocities down stream. The retention basin also settles out some solids. By allowing pollutants to settle out of the stormwater and preventing additional pollutants from entering the stormwater via erosion downstream, this BMP helps to improve the quality of Logansport’s stormwater. In addition, catch basins are located throughout the Logansport storm sewer system. These catch basins are designed to allow sediment and other heavy materials to drop out of the stormwater before they are conveyed along the storm sewer. This BMP prevents a majority of pollutants from being transported through the conveyance system, thus improving the quality of Logansport’s stormwater. An initial evaluation of nonstructural BMPs was performed as a part of the Part B submittal process. The current nonstructural BMPs are generally described in Chapters 3 through 8. The existing nonstructural BMP programs were reviewed for sufficiency. The programs were altered as necessary to comply with the requirements of Rule 13. 1.8 Current Land Uses Industrial Areas : The industrial areas identified are shown on the MS4 Conditions Map within Appendix B . These will be visually monitored for potential pollutants during the ongoing characterization of this plan. Additional data gathering from monitoring points along the receiving streams may generate additional key observations. Agricultural Areas : The agricultural areas investigated are shown on the MS4 Conditions Map within Appendix B . These areas will be visually monitored for potential pollutants during the ongoing characterization of this plan. As data is gathered from monitoring points along the receiving streams, additional key observations may be generated. Existing Monitoring Points : Existing monitoring points and monitoring data were evaluated. It was found that the existing monitoring points and their corresponding data do not allow for conclusions to be made about land usage and their effect on stormwater quality. Additional monitoring points and additional water testing associated with these monitoring points is proposed. Proposed monitoring locations are shown on the M MS4 Conditions Map , Appendix B . 1.9 Sensitive Areas Sensitive areas that may need added water quality protection considerations may include the following: · The public surface drinking water intake that is located upstream of the 10th Street Dam on the south bank of the Eel River; · The Eel River; it is listed on the State of Indiana's "Outstanding River List" for canoeing and boating. It is not however on the “Outstanding State Resource Waters List;” · The Wabash River; it is listed on the State of Indiana's "Outstanding River List" as a Heritage Corridor. It is not however on the "Outstanding State Resource Waters List;" · The public access site on the Eel River, located just upstream of the 10th Street Dam which is used for fishing, swimming and launching canoes; · The Wabash River for canoeing; · Additional areas within the Eel and Wabash Rivers for swimming, however there are no designated swimming areas or beaches. · The Little Turtle Waterway Plaza, for fishing and the Ducky Derby during the Heritage Festival; · The many bridges that cross the Eel and Wabash Rivers for fishing; and · Goose Creek for its swan habitat which is otherwise located on private land. These sensitive areas are shown on the MS4 Conditions Map in Appendix B . 1.10 Areas Having Reasonable Potential for Causing Water Quality Problems Correlative conclusions between existing water quality data and potential problem areas could not be made from the existing data that was gathered and analyzed. Monitoring point locations were recommended in an effort to gather more useful data. With the new data, identifying water quality problem areas should be possible by the end of this 5-year permit term. The City's ordinances establish legal authority to carry out such activities as inspection, surveillance, and monitoring or enforcement procedures necessary to ensure compliance with the minimum control measures (MCMs) identified in the following chapters. 1.11 Identification of Areas Causing Stormwater Pollution from Existing Water Quality Data Existing water quality data was inconclusive; therefore, areas suspected of causing stormwater pollution could not be identified. Monitoring point locations were recommended in an effort to gather more useful data. With the new data, identifying areas causing stormwater pollution should be possible in this 5-year permit term.
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Logansport Municipal
Utilities 601 East Broadway #101 Logansport, Indiana 46947
Telephone: (574) 753-6231 |