FAQs
Can you provide a general overview of the project including the location of the sand donor site in relation to Bathtub Beach?
This project involves the restoration of the vegetated dune system at Bathtub Beach Park. This project is necessary to provide some stability to a very dynamic dune and beach system in an effort to encourage the buildup of sand on the beach. The sand that will be used to create the dune system will be moved from a shoal area inside the St. Lucie Inlet. Sand carried by ocean currents typically moves from north to south and into inlets (diagram below), so the sand identified at this donor location is similar in characteristics to that on Bathtub Beach, making it the best choice for replenishment of the dune system.
In this diagram, the arrows depict sand movement from north to the south, with substantial settling of sand inside the inlet on the shoal, just south of Sailfish Point.
The diagram above depicts the proposed donor site, based on seagrass avoidance. You can clearly see the sand deposits in both diagrams.
Why are you limiting the project to a dune system only?
The project will mimic nature by rebuilding the dune that has existed on the site historically. The beach has naturally varied in size over the years, dependent upon wave and weather patterns, and this will continue after the project is complete. The county’s main goal is to protect the infrastructure at Bathtub Beach by rebuilding and revegetating the dune so that the public can visit the park once again. One of the most popular amenities at the park is the nearshore wormrock reef. A larger project could directly cover the reef, causing significant harm to the sensitive ecosystem.
Where are you going to find compatible sand for the project?
An important component of this project is locating sand that closely matches the sand naturally found at Bathtub Beach. We have selected the flood shoal just inside the St. Lucie Inlet because it contains sand that actually came from the beach (see diagram 1 and 2 above).
Boaters should be careful when dredging equipment is in the area of the sandbar. The dredging operation will not impact any areas that are above the MHWL and will focus on the south side of the sand bar area currently used for recreation.
It seems like the County just completed a project at Bathtub Beach. What happened to that sand?
The dune that the County is restoring has maintained itself intact for quite a long time. Even back in 1999 when there was major erosion at Bathtub Beach, the dune remained relatively undisturbed. A constructed vegetated dune that closely matches the natural dune in dimensions and composition, should remain stable and provide a foundation for sand accumulation at Bathtub beach. The storm that impacted this beach in 2007 was very unique – something we haven’t seen historically at this site. In this particular case we had a September with 2 full moons – a time of year when we expect extreme high tides naturally. When the moon is as perigee, the range is increased and when it is at apogee, the range is reduced. Every 7 1/2 lunations, perigee coincides with either a new or full moon causing perigean tides with largest tidal range. It a storm happens to be moving onshore at this time, the consequences (in the form of property damage, can be severe. This phenomenon was coupled with strong, sustained winds out of the east, further raising the water level. The protection normally afforded to Bathtub Beach by the natural reef system did not occur. The unusually high water levels completely submerged the reef, and eliminated it’s wave breaking function. Instead, waves riding on top of this elevated water level progressed past the reef line and were able to break on the dune – and directly into the vegetation. It was a unique combination of extreme tides, water level and wave direction that caused the rapid changes at Bathtub Beach in September, 2007.
Why will it take so long to get this project completed?
This project needed to be designed to avoid impacts to nearby environmentally sensitive areas. The County had to collect the necessary data in these areas to guard against unforeseen impacts to valuable resources. The data was gathered and analyzed, a project design was developed and the County has received the permits. The contractor has also been selected and they are set to begin construction in early March 2010, finishing construction prior to sea turtle nesting season on May 1, 2010.
How much will the project cost?
The County has funding available for this project and the State has committed to cover 50% of the needed project funds. The selected bid for the project was $552,500.00
What are the other environmental concerns in this area?
The key environmental concerns include the near shore worm rock reef, sea turtle nesting and foraging habitats, and seagrass habitat at the donor site. The worm rock reef is described above and is also important due to the utilization of the reef system by sea turtles and many fish species for providing habitat and a food source. When the project is complete and more sand accumulates naturally to the site, sand will be available for nesting sea turtles – important since there isn’t currently a dry beach. Finally, seagrasses are important estuarine habitats that provide habitat for juvenile fish, manatees and other important species. The county’s consultants have surveyed the selected donor site and have identified locations of sea grass beds. A minimum of a 100' buffer will be placed between and sea grass bed and areas where sand will be removed.
What type of monitoring is ongoing?
To prepare for and be in compliance with the state and federal permits, the county is monitoring seagrasses, migratory birds, sea turtle nesting, the nearshore reef system, and land and bathymetric surveys at and around Bathtub Beach. Once all of this information is available, it will be posted on the website for public review.
