LONG BEACH — Efforts to launch a restoration project of the Naples Island canal have been stalled again as the city undertakes a new engineering study.
More than 250 Naples Island homes are considered vulnerable to flooding if the 107-year-old seawall crumbles during an extreme storm or an earthquake, a city engineering study warns.
The city has $9.5 million to begin the seawall renovation, but the project has been stalled over environmental issues related to reinforcing the wall either on the water side or the land side.
After discussions with Coastal Commission staff, city officials agreed to evaluate through a geotechnical study the feasibility of a land-side renovation, according to Eric Lopez, Tidelands capital projects program manager.
The study could take up to six weeks and cost up to $50,000, Lopez said Monday.
"It's a work in progress," he added.
Before the restoration project can get under way, the plan must first pass muster with the Coastal Commission.
City officials have notified the commission staff that they want to do the repairs on the water side.
However, earlier this year, commission analyst Chuck Posner said the push for restoration in the canal waters could have negative impacts on marine eelgrass. That would require a mitigation plan, he said.
Experts also say that water-side restoration would require 13 palm trees to be uprooted.
Work on the land side, however, would require removing 67 palm trees, which some environmentalists say are nesting sites for exotic egrets and herons.
The water-side repairs would also improve the "seismic capacity of the seawall and protect the value of adjacent residential properties," a city report states.
The land-side repairs, on the other hand, are designed to have the "least impact on ... channel depth, channel width and eliminate corrosive materials from the construction," the report says.
The canals were dredged in 1905, and the original walls were constructed of wood in 1923. However, the walls were damaged in the 1933 earthquake.
Pre-cast concrete walls were constructed in 1938-39, and through the years, until the early 1960 s, the walls sank underwater 1.5 feet, according to a Public Works report. High tides, the report added, had crested over the seawalls.
The seawall system is divided by planners into three segments: Naples Island, where about 82 properties and Colonnade Park front the water; Landside, which has about 133 waterfront properties; and Treasure Island, which has 39 properties on the water.
In 2010, the council earmarked $9.5 million for the Phase 1 work to fix the most deteriorated part of the wall.
Repairing the entire canal structure would cost an estimated $60 million, to be completed in six phases.