Walmart seeks to add supermarket at another Long Island store

Walmart is the nation’s biggest seller of groceries, but it doesn’t even crack the top five on Long Island, where supermarket competition is fierce and growing.

So, Walmart again is seeking a bigger slice of Long Island's grocery sales by planning to expand its Islandia store into a supercenter with a full-service grocery store — in a shopping center that lost its Stop & Shop supermarket three years ago.

Walmart has gone the expansion route before on Long Island. Two of its three supercenters — in Valley Stream and Farmingdale — started out as regular discount stores before growing with the addition of supermarkets more than a decade after originally opening.

“Walmart is going to reap more than double in sales [with a supercenter] versus a conventional discount store, which they operate