Minimum Flows for the Tampa Bypass Canal, Tampa, Florida

Army Corps of Engineers for the purpose of flood control in the Hillsborough River basin. This included excavating the bed and banks of Six Mile Creek/Palm River, as well as substantial parts of the floodplain, leaving no instream or riparian habitats intact and greatly expanding the width, depth, and volume of the native drainage. The Southwest Florida Water Management District has made two attempts to study the effects of freshwater inflows in the TBC and to evaluate the need for a minimum flow level in this floodway. These studies were conducted (1) because Florida Statutes (§373.042) mandate the District's evaluation of minimum flows and levels (MFLs) for the purpose of protecting the water resources and the ecology of the affected area from " significant harm, " (2) because the original area had once been a part of a tidal creek with a functional estuarine nursery that helped produce an abundance of seafoods of commercial and recreational interest in the Tampa Bay area, and (3) because of the continued expansion of municipal and industrial water diversions from the area to meet the ever increasing water demands of the fast growing Tampa coastal region. In the end, the District's net conclusion is that the TBC flood control system is so highly altered that resource protection will be difficult if not impossible to achieve by water flow management alone and, therefore, the District declined establishment of a minimum flow level for the TBC at this time. The District's goals, indicators, and definitions, as developed and explained in the subject report seem reasonable and appropriate to the Review Panel. The District's conclusion that an MFL for mangroves in McKay Bay is unnecessary is also well justified since there is no technical disagreement that mangroves can tolerate very high salinities, and that the soil salinity is not directly proportional to surface water salinity in mangrove 3 wetlands. The Review Panel supports the District's conclusion that an MFL for oysters is not warranted as well because (1) the oysters can tolerate existing and future salinity ranges in the TBC/McKay Bay complex, including the salinities expected when TBC discharge is zero; (2) increasing stratification and decreasing dissolved oxygen with increasing TBC flows is contraindicated for oyster survival, growth, and reproduction; (3) much of the oyster mortality in the area appears due to high flood flows which decrease salinities to lethal levels; and (4) shellfish harvesting in McKay …