An interim flood pulse for the Kissimmee River Restoration Project
David H. Anderson, Watershed Management, South Florida Water Management District, 3301 Gun Club Road, MSC 4460, West Palm Beach, FL 33406
The pulse-like inundation of the floodplain is recognized as a key driver of river ecosystem dynamics, and reestablishment of the flood pulse is critical for successful restoration of the Kissimmee River in Florida. Restoration of the flood pulse will be accomplished with a new stage regulation schedule (headwaters revitalization) that will increase water storage in upstream lakes and operational flexibility for the release of water to the river. Since the first phase of the project was completed in 2001, an interim regulation schedule has been used, which has intermittently inundated the floodplain. During the six years of the interim schedule, 12 flood pulses were measured near the upstream terminus of project construction. These flood pulses crested 0.2 – 1.8 m above average floodplain elevation of 12.2 m NGVD. Only 3 pulses exceeded the 173 day minimum threshold for desired duration. Only 4 pulses had recession rates that approximated the target of < 0.3 m/30 d. These results suggest that the flood pulses under the interim regulation schedule occur more frequently, are shorter, and recede faster than the pre-channelization system. Consequently, full restoration of floodplain plant and animal communities is unlikely until the headwaters revitalization schedule can be implemented when construction ends.