Housing markets in California have made a stunning about face: Lenders  there now may face a housing shortage instead of the glut of a few years   ago.   In a recent paper entitled, "Thinking the Unthinkable: Housing Shortage   on the Way?" the California Association of Realtors warns that a scarcity   of affordable housing could dampen economic growth, now that more Americans   are expected to move to the state than leave.   For the first time in five years, net domestic immigration to California   will be positive in 1998, as residents of other states flock to thousands   of new high-tech, entertainment, and software jobs, according to the   Business Forecasting Project of the Anderson School at UCLA, Los Angeles.   "Serious supply shortages are already emerging in areas where economic   growth has returned the fastest and are likely to spread as the California   economic expansion broadens," writes the Realtors' deputy chief economist,   G.U. Krueger.   The group is worried because the new building permits, which fell   precipitously in the '90s, are projected to increase only slowly for the   rest of the decade.   For lenders, though, a tighter housing market in a state that last year   accounted for 17% of all mortgages would be good news. Scarcity already is   driving up the value of homes that collateralize the loans. That means   larger-and safer-home loans, says Mark Zandi, chief economist of Regional   Financial Associates, West Chester, Pa.   For homeowners who hit a financial roadblock and want to bail out of the   mortgage, appreciating home prices are a big plus, says Terrance G. Hodel,   president of North American Mortgage Co., Santa Rosa.   They can sell the home and repay the loan, he says. Falling home prices   during most of the '90s have left owners holding mortgages larger than the   value of their homes, and many financially troubled borrowers have opted   for foreclosure.   A housing scarcity and price gains also boost the demand for related   lending, such as construction loans to builders and home equity loans to   newly enriched homeowners.   Eventually steep price increases could pave the way for a painful   correction. California "has a history of developing price bubbles that   eventually pop," Mr. Zandi notes.   But he adds the state has "a ways to go before we see a speculative   house price bubble developing."   Since 1991, 90,000 to 110,000 permits have been issued annually.   Permits, which peaked at 238,000 in 1989, will increase to only 144,000   permits in the year 2000, according to the UCLA Anderson Forecast. That's   not fast enough, Mr. Krueger argues, to keep pace with California's   population growth.   Higher population density and steep price appreciation are already   surfacing in the state's northern half-in San Francisco and the Silicon   Valley county of Santa Clara, for example, agrees Tom Lieser, associate   director of the UCLA Anderson Forecast.   "San Francisco has reached the point where (a) lack of affordable   housing could be a real constraint to the growth of business," Mr. Lieser   says. Seattle, Los Angeles and Sacramento may siphon some of the growth, he   says.   Mr. Krueger and others blame the anti-growth stance of the state's   metropolitan areas for the fact that permits won't pick up faster. Many   counties require builders to help pay for schools, roads and water lines,   he says. Expensive legal challenges by neighbors to new developments also   slow the pace of building.   Mr. Lieser of UCLA thinks another factor is at work as well-developers   are still nursing memories of the real estate crash of the early 90s.   "It's kind of difficult to kick a new housing boom off. Builders first   need to be persuaded profitability has returned," he says.   He adds another reason: "There may been some reluctance by banks to   finance what might have been until recently a premature construction   cycle."   Some California-watchers think this talk of impending housing shortages   is overblown.   "I just don't believe it," scoffs Michael Carney, professor of finance   and real estate at California State Polytechnic University, Pomona.   Except for a handful of northern counties, most still have weak home   sales and lots of foreclosures, Mr. Carney says.   If the strong price increases in Northern California spread to the rest   of the state, "builders will respond, and we'll have a big surge in housing   permits."   Still, he too, worries there are too many constraints on new home   building.   Eventually, the market will respond, Mr. Krueger agrees-but with a lag   of two to three years: "Its timing will not be what you need in a modern   economy."