A Bay Area developer is considering downtown Petaluma to be the location of its next affordable housing project. MidPen Housing of Foster City wants to build 40 affordable rental apartments at 414 Petaluma Boulevard. The nonprofit developer is hosting a series of meetings in the area, seeking community feedback. MidPen officials say they will come back with a site plan in November. Developers hope to submit an application to the city early next year and start construction in mid-2020.