Almost 50 percent of all new homes in San Joaquin County are being built in Manteca-Lathrop.

And with sales at the 11,000-home planned community of River Islands at Lathrop picking up steam, the Manteca-Lathrop share of countywide housing growth is expected to get even bigger.

Manteca-Lathrop developers built 577 homes in 2014 or 47.4 percent of all new homes in the county. Since 2008, the two neighboring South County cities have accounted for at least a third of all new homes in San Joaquin County. The local share of new home construction peaked in 2010 at the depth of the Great Recession when the Manteca-Lathrop share was at 57.3 percent or 495 of the 801 homes built in the county’s seven cities and rural areas.

The data gleaned from annual building statistics for the cities as well as the county has had Manteca as the top city for new homes in the county since 2008 when 239 of the 770 homes countywide were built in Manteca. Between 2008 and 2014, some 2,014 new housing units were built in Manteca including 2,402 traditional single family homes and 204 apartments. During that 7-year period Manteca added almost 8,000 new residents or almost 60 percent of the current population of Ripon.

In the first four months of the current year Manteca builders have started 274 new homes. They are on pace to push 350 new homes by the time 2015 ends. The new homes being built so far this year in Manteca are averaging 3,181 square feet.

Site work is currently underway on four new neighborhoods south of Woodward Avenue.

While Manteca is expected to keep building 300 plus homes a year,  River Islands at Lathrop is in position to match that and possible even exceed Manteca’s overall total annual new home building in the coming years.

 After less than a year of sales, builders at River Islands have sold just over 300 homes.

A third of the purchasers are move-up buyers from Manteca and Lathrop, a third are from Mountain House and Tracy, and the remaining third are Bay Area buyers. River Islands is designed as a community with a built-in lifestyle with relatively small lots.

River Islands is getting ready to release another 400 lots to builders.

Cambay Group — the firm that owns River Islands — is preparing to develop another 1,000 lots in 2016.