TITLE
Recommendation to request City Council to fund the Naples Seawall project with $9.5 million of Tidelands funds.
DISCUSSION
During the April 6, 2010, Naples Seawall study session the stability of the seawall infrastructure was discussed. From this study session it was made clear that the walls are in eminent danger of collapse.
The seawalls were first constructed in 1905, and then damaged in the 1933 earthquake. The Works Progress Administration rebuilt the seawalls in 1938. Over the course of the subsequent three decades, 1.5 feet of subsidence was recorded with high tides cresting over the seawall. In 1967, an 18-inch cap was added to the top of the original seawall. During the 1980's and 1990's, voids and seawall movement was detected and it was discovered that the tiebacks were failing. Over the past decade, the tiebacks were replaced at critical locations. Lastly, a 2009 study revealed vast deterioration of lower seawalls.
Due to the serious infrastructure concerns, the City has proposed to conduct the Naples Seawall Interim and Long Range Repair Project. The existing 11,000 lineal feet of seawalls are 70 years old and in need of replacement. The expected remaining life is 5 to 10 years. Full replacement at the most deteriorated sites would fully mitigate the immediate structural issues. The options are either waterside repairs (new concrete wall with sheet piles) or landside repairs (new synthetic wall with tie rods). Construction of replacement walls is estimated to require $9.5 million, and replacement of the entire seawall system is currently estimated at $60 million.
The Planning Commission approved the Mitigated Negative Declaration for the Interim and Long Range Repair Project on May 6, 2010.
SUGGESTED ACTION
Approve recommendation.
Respectfully Submitted,
COUNCILMEMBER GARY DELONG
THIRD DISTRICT
COUNCILMEMBER SUJA LOWENTHAL
SECOND DISTRICT
COUNCILWOMAN GERRIE SCHIPSKE
FIFTH DISTRICT
VICE MAYOR VAL LERCH
COUNCILMEMBER, NINTH DISTR...
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