BRADENTON — At Tuesday’s land use meeting, Manatee County Commissioners received an update on the status of Lake Manatee following reports of widespread flooding in the area on Wednesday evening.
Deputy County Administrator Evan Pilachowski, who oversees Utilities, Public Works, and Financial Management, addressed commissioners and led with the following statement.
“I do want to state unequivocally that the dam and Lake Manatee continue to function as designed. They are structurally sound. There’s no risk of any sort of breach of the damn. I just want to make that clear.”
Pilachowski explained that the area experienced the second day of significant rainfall in and around the dam watershed. He said widespread areas received three to four additional inches of rain and isolated areas received six to eight inches, all in about 36 hours.
Pilachowski said that soils are saturated, stormwater ponds are full, and culverts are at capacity. With significant rain falling on an already saturated rainwater system, the water simply doesn’t have anywhere to go but to continue to run over land, and the flooding on Waterline Road and Dam Road is owed to the system being saturated and overloaded.
Pilachowski stressed that the dam is not a flood control structure but that the county does try to provide some relief and buffering from the Manatee River flows with the dam where it can.
Since Hurricane Debby, Pilachowski said the county has maintained the secondary spillway at 38 feet, meaning that any water entering at that capacity flows through because there is no storage capacity available. He said the flow in and out of the lake are equal. In other words, it is not water coming “from” the dam, but water moving “through” it. He said the county is looking at providing some temporary measures at the secondary spillway to provide some level of buffering.
Pilachowski told commissioners that at around 7 p.m. Wednesday, flows in the river leading into the lake were increasingly rapid, with a flow rate of 3,500 cfs. “At those levels, we know that there are 14 property owners downstream that have impacts.”
Pilachowski said the county communicated directly with property owners, and as the flow rate increased, the county made contact again. However, he stressed that it was not a warning of an active release but responding to monitoring flows to provide information to warn impacted properties.
When the county learned through social media posts that additional homes in the area were being impacted, he said staff posted another message to the county's social media pages. Hours later, he said they received reports of standing water at Waterline Rd and Upper Manatee River Rd and sent out public works crews to barricade the roads, and another social media message was posted.
Pilachowski said the county is looking for areas where it can improve. He said they are working to implement an after-hours number and getting sandbags to downstream residents. He added that the county is also considering lowering the target level below 38 feet in the short term. He reminded commissioners that the dam is primarily a source of drinking water for residents, so they had to be careful when weighing lower levels. Nevertheless, he said he believed levels could be lowered to provide relief during the wet season, with enough recaptured for storing during the dry months.
Pilachowski closed by again stressing that the dam was not in danger of breach or collapse.
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ducks4u
Apparently he didn't read the previous report on the condition of the Manatee Dam and what was needed. Same old run around by Manatee Government.
Thursday, August 22 Report this
WTF
All the technology that the county claims to have in preventing flooding and all the models that they should have been running prior to this storm just tells me the level of incompetency of staff. Newsflash we were in Florida. We get hurricanes be prepared at every level. Truly, it parallels a hurricane as a failure at a catastrophic level… For the record
Thursday, August 22 Report this
nellmcphillips
The hurricane season is far from over and there needs to be some serious work done on the long term sustainability of this dam as well as a significant maintenance and repair plan that has long been ignored. Bring in some dam experts and figure out how to get us through this hurricane season and into the future. The BOCC ruling philosophy of build, build, build has lead us down a disastrous path. The County needs a plan now!
Friday, August 23 Report this
MorrisonL5
In Pennsylvania, all new development is required to keep all rain/stormwater on site. A developer is not allowed to let the storm water go off site on to neighboring property. Storm water is rain water from new roofs, driveways, patios, new roads, etc. - all newly built impervious surfaces. Large, DRY retention basins are required to be built ON THE NEW DEVELOPMENT, and all the rain water flows to pipes to empty in the retention basin. Basically they are big DRY holes, usually lined with grass - some are "rain gardens" that are lined with wetland-type plantings.
I don't understand why FL allows water-filled ponds as "storm water management." The pond is already water filled. So, it can't accept that much more water in a heavy rain....? Maybe someone can explain.
Friday, August 23 Report this
David Daniels
Don’t let them forget we want an independent investigation of what happened during Debby. Charlie Bishop and the administration should be held accountable. An investigation should also include recommendations and a process to follow, including standardized, defined warning language and warning targets.
Friday, August 23 Report this
rayfusco68
This isn't rocket science folks. The reservoir water level should have been reduced at the start of the rainy season to a significant level that would have allowed further lowering when the weather gurus predicted large rainfalls approaching. The lake isn't our only source of potable water. The emergency spillway should also spill into a canal designed to contain the water flow and direct it to a safe location, such as the bay or a secondary empty dam enclosure. All new construction should stop until this problem is resolved. Just as important is the contamination of the Gulf, rivers and estuaries with sewage overflow. This also needs engineering solutions. This is what happens when you allow developers to do as they please and not pay full impact fees to address these issues before they become a public emergency and a tax burden on the citizens of Manatee County
Friday, August 23 Report this
ducks4u
In spite of Holmes Beach Code and Comprehensive Plan (quoted below) and repeated resident monitoring and communication, neighboring properties still get flooded. Enforcement is needed.
"New development or redevelopment shall be responsible for on-site management of stormwater run-off in a manner so that post-development runoff rates, volumes and pollutant loads do not exceed existing conditions.
While development activity is under way and after it is completed, the characteristics of stormwater runoff shall approximate the rate, volume, quality, and timing of stormwater runoff that occurred under the site’s natural unimproved or existing state, except that the first one inch of stormwater runoff shall be treated in an off-line retention system. Retention areas should ensure the probability of flooding either upstream or downstream owner’s property is not increased."
Friday, August 23 Report this
imjojo
The Army Corps of Engineers should be called for an assessment!! PERIOD!
Tuesday, August 27 Report this