Future condition and concerns for the planning area portion of the watershed were gathered using a variety of data sources. All resources are referenced in Chapter 7 of this Master Plan. Supporting documentation on water quantity data listed below can be found in Appendix 2 and water quality in Appendix 3.

• Current allowable release rates provide the “factor of safety” intended by the ordinance and are expected to be adequate to prevent increases in the 1% to 10% annual chance flood peak discharges.
• No control on the 50% annual chance flood developed condition discharge has been or is in the Town or County current ordinances. Based on a study of the Williams Creek watershed in Hamilton County, development under the current ordinance allows for substantial increases in the 50% annual chance flood. Not only does the ordinance allow increases in the peak discharge but also in the duration of the flood. The 50% annual chance flood is typically the channel forming discharge for streams. When that flood frequency increases in discharge and duration, additional stream bank erosion typically occurs. Such erosion affects not only the stability of the bank and the safety of anything on the bank but the quality of the water as well.
• Along White River, structures appear to be built on bluffs that are well above the 1% and 0.2% annual chance flood elevations. Future conditions along White River are not expected to cause flooding of additional structures. Once the new preliminary FIS maps are finalized, modeling results for Shoemaker Ditch can be utilized to determine any potential flood impacts from increased runoff, should that happen to occur in the future.  At present, available studies are insufficient to analyze impacts on the remaining small streams.
• Impact on roads/bridges - no change expected.
• This watershed is considered to be fully urbanized with little change to the current land use. Based on available future land use data, approximately 10% remain as municipality owned nature preserve, park, and cemetery. Development for Riverplace and Exit 5 Technology Park will increase the residential and commercial land uses as will the future transit-oriented redevelopment plans for the Indianapolis Metropolitan Airport. Depending on how the airport is redeveloped, imperviousness is estimated to increase from 89% to 93% which remains indicative (typically) of poor water quality.
• Since little change in land use is expected, it is anticipated that water quality in some or all water bodies will likely continue to be impacted by elevated nutrient, bacteria, total suspended solids, and metals loads.
• Current Stormwater Management Ordinance requires post- construction BMPs to remove 80% Total Suspended Solids (TSS) from stormwater runoff. It is assumed that other pollutants of concern will be captured to some extent with TSS. Elevated E.coli and Impaired Biotic Communities violations, as noted in 303(d) Impaired Streams List for the White River, are not addressed.