Extensive drainage improvements are planned for the area surrounding eastern Shore Drive, from First Landing Park on the east to Lynnhaven Inlet on the west. As background, this area was originally developed without a comprehensive storm water management system (pipes, outfalls, etc.), and as a result has been impacted by repetitive street flooding during rainfall events over the years. Infill development has increased the basin’s imperviousness, and has worsened the situation. In addition, a large portion of the developed drainage basin is relatively low, and as a result is subjected to tidal inundation during storm events with higher tides. The lack of an original storm water system to “improve” and the impacts of direct tidal inundation combine to increase the cost and complexity of improvements for the drainage basin. It is anticipated that the improvements will include improved systems of pipes and inlets to collect the storm water runoff, backflow prevention devices to block higher tides, storm water pump stations, and fill for berms, dikes and diversions.
The project is currently in the analysis/conceptual design phase, which is scheduled to be completed in December 2016. The next steps will include presenting the concept plan to the public for input, preparing the design documents, advertising, and constructing the individual phases as available funds allow.
In addition, a separate study was prepared to determine if check valves or tide gates could be installed at critical locations as an interim measure. The interim study was issued on June 18, 2013. The Bayfront Advisory Committee (BAC) was briefed on June 20, 2013. The interim study and BAC presentation are available by clicking on the below hyperlinks. Authorization to design and construct the proposed interim measures was issued on September 3, 2013. Installation of check valves at 5 locations in the Lynnhaven Colony Tidally Adjacent area occurred early 2014. Construction of 3 sluice gates along the Cape Henry Ditch is scheduled to occur from January to September 2016 after detailed engineering and obtaining environmental permits. The schedule for the 3 sluice gates is contingent upon no easement acquisitions, significant permitting requirements, or other deterrents. While these interim measures are able to offer some level of tidal flood protection, there are limitations at which point overland tidal flooding will occur and the low-lying areas cannot be protected.
Posted April 30, 2014