Charlotte has a shortage of affordable housing, according to several studies oft-cited by city and county officials, but getting developers to build more has proven difficult. Tonight the Charlotte City Council will begin debate on a plan to give builders incentives if they include affordable units in their projects. If you were to take a map of Charlotte and color code the neighborhoods according to income level, you'd see a pretty clear pattern of "income segregation." That's Mary Klenz' term. She's chairwoman of the Mixed Income Housing Coalition which advocates for just what its name suggests. Klenz says income segregation that has developed over the years keeps poorer people from having access to jobs, good schools and even health food stores. The city would like to encourage more mixing, rather than the old model of building low-income housing projects. Mayor Anthony Foxx wants the city to offer incentives to builders so they'll include some affordable units in their developments, alongside apartments and condos that sell for top dollar. The city council has a preliminary list of incentives that includes waiving development fees and fast tracking permits for such projects. That's a start, says Ken Szymanski of the Greater Charlotte Apartment Association, 'but I think most would say it may not be a deep enough series of incentives . . . to make a developer act." Szymanski says developers will need more money to cover the loss they'll take on affordable units. Tax credits and low-income housing subsidies already exist for such projects, but competition is stiff. Making more money available to developers is not on the list of incentives the City Council will review tonight. However, the council plans to form a Citizens Advisory Group to flesh out the details of the policy this fall, including exactly what "affordable" means. A final policy will be in place next spring.