Guest: Nancy Shaver on conditions of sea-level rise

Former Mayor Nancy Shaver may be one of Historic City News’ best qualified sources of current information and most familiar with the resiliency issues facing St. Johns County.  While in office, she traveled as part of a Florida delegation to the Netherlands to learn first-hand about technological solutions to sea level rise, including resiliency measures for nuisance flooding and storm surge.

That said, she recently distributed her commentary regarding what she described as rapidly upcoming conditions of sea-level rise.


I have followed the progress of the San Sebastian PUD with some concern. There appears to be little consideration by staff or boards of the known impacts of sea-level rise on both roadways and sewer service for this project.

The City has comprehensive information about those rapidly upcoming conditions, which should be considered in these deliberations. The Coastal Vulnerability Assessment of 2011 outlines the risks to this project clearly.

As a member of the American Flood Coalition, the City has received additional confirmation of the risks. The Planning and Zoning Boards also received comprehensive briefings on the subject. I am not certain they understand the legal risks to the City of a less than comprehensive application of the information at hand.

The Vulnerability study includes comprehensive projections of sea-level rise. The NOAA high model is the most conservative guideline and protects the City best from legal challenges. Lakeland is currently involved in a lawsuit regarding a failed project that relied on the Army Corp models.

Given that projects of this type have a long horizon, here are the known risks according to the information the City holds.

Roadways and Bridges:

  • The San Sebastian PUD area can expect 1.5 feet of sea-level rise during the next 9-10 years. The details of those impacts and upcoming failures are outlined in Section 4 of the Vulnerability Assessment.
  • Failures include nuisance flooding on 30% of the city roadways including frequent failure of the King St Bridge, making access to the project problematic. This will occur 25% of the time by 2031. The rise will increase rapidly with bridge and road failure at 2 feet of sea-level rise by 2040 (pgs. 20-24).
  • Mitigation is neither practical nor affordable. The failure of the Coquina effort in the recent flooding was a clear and expensive demonstration of that.

Sewer Service:

  • The wastewater plant vulnerability has been documented and despite some modest recent efforts will experience total failure in 9-10 years at between 1 and 1.5 feet of sea-level rise. (pg.36)
  • Without the Commission and the project developers having a clear understanding of these immense risks to a multi-million-dollar, multi-year project, it would seem to create a significant risk to all.
  • Florida cities with similar foreseeable risks have created Adaptation Action Areas to both protect themselves and property owners. Parts of Jacksonville have been so designated. It would be wise to explore the feasibility of those options.

In the meantime, I suggest you put a hold on “up-zoning” areas of Saint Augustine. A pause would seem to be in everyone’s interest.

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