The Newport Beach City Council approved a contract Tuesday to increase the height of the seawalls that protect Balboa Island.
The roughly $1.8-million project breaks down to $1.4 million for construction and about $350,000 for contingency, consultant services, materials and geotechnical testing and incidentals.
Chatsworth-based Bosco Constructors will add a 9-inch concrete cap to about a mile and a half of the publicly maintained seawalls on the north, south and west sides of the main island.
The cap will help protect the community from flooding during especially high tides, officials say.
The item passed 6-0 with no discussion, with Councilman Jeff Herdman recusing himself because he owns property on Balboa Island.
Work is expected to start in November and be finished by the spring, with a hiatus during the holidays and the Newport Beach Christmas Boat Parade.
The extension, which would bring the walls to 8½ to 9 feet tall, is a less-costly measure in place of replacing the aging walls.
The walls were built between 1929 and 1939 and are considered to be in fair condition, with some superficial cracking and pitting. With continued maintenance, they should have 10 or more years left in them, according to a city staff report.
The new project will make the main island's walls about as tall as those on Little Balboa Island, which the city capped in the late 1980s.
To maintain existing access to public beaches, the city will leave a gap at all 29 street ends and at the four public docks. During high tides and storm surges, temporary barriers will be installed across the gaps.
Installation and removal of the temporary barricades and maintenance of the gap openings will require an estimated $50,000 per year.
To minimize closures of the public boardwalk during construction of the cap, it will be built in phases across 17 work areas. Each work area will be about 450 feet long, and construction will occur at no more than three non-consecutive work areas at any given time. Work in each area is expected to take 10 to 15 work days.
Peninsula crosswalk study
The council postponed its review of the results of a Balboa Peninsula crosswalk safety study because other discussion items ran long. The crosswalk study will return to the council for its Oct. 24 meeting.