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DRAFT more thorough hydraulic analysis employed in this latest study showed the effects of the constrictions more accurately leading to a larger floodplain. Velocities were found to be slower than in previous analyse:; which also led to greater flood depths. The result was that less water really did produce a larger floodplain. Modifications to the Floodplain In the spring of 1993 we learned from the LMMP study contractor that there had been some filling in the Oak Creek floodplain, in the area being studied, In of 1993 a FEMA representative visited Florence and discussed the filling activity with City officials. In June of 1993 Brian Hyde toured the site on behalf of the CWCB and then attended a meeting with City officials, FEMA officials and others. Despite the fact that the City and the developers were aware of the LMMP study in progress, they did not notify the study contractor, FEMA or the CWCB of the filling acti vity as it was going on. From appearances two feet or more of fill have been imported to the site, so the topographic change is substantial. We believe that the filling began sometime after the May 1992 meeting and was completed by the spring of 1993. Some understanding of the peculiarities of this particular floodplain would explain the importance of the change brought about by this filling. As Oak Creek enters Florence, it encounters some undersized bridges. About half of the flow is diverted either to the right (east) or to the left (west). The diverted water flows overland at depths of about two feet or less. Some water returns to the channel and some does not. The development site represents one large area for this overland flow. When a large geographic area is subject to flooding, even if it is shallow flooding, the amount of water is substantial. In this particular case the amount of water is in the thousands of cfs, so the situation is not trivial. If such a large area is filled deep enough in order to protect it from flooding, the water that would flow there would have to go somewhere else, unless specific provisions are made to convey it safely through the filled area, We are not aware of any engineering that guided the filling, so we assume no provisions were made for the water that would be diverted by the filling activity. Where that water would go has not yet been determined. Floodplain Development Permits Communities that participate in the National Flood Insurance Program, as Florence does, are obliged to require floodplain development permits be obtained prior to any "development" in the floodplain. The permit application materials submitted by the proponent have to include some technical information, That technical information has to be sufficient to allow the local permitting official to determine whether the proposed activity would comply with the community's regulations. The need to require floodplain development permits has been conveyed to the City Manager of Florence on several occasions, Mark Matulik has conducted visits on and told the City Manager of that. FEMA officials and other CWCB representatives have also told the City that. The most recent time this message was conveyed was at the June 1993 meeting mentioned above and in the July 1993 letter that followed that meeting. Despite all of those efforts to remind the City of what is in their own regulations, there is still no permit for the filling that has already transpired. To our knowledge no permit application ha" been submitted.