SAN FRANCISCO (KCBS)— Affordable housing activists wanted a measure on November’s ballot, making it hard to for developers to build unless one-third of the new housing is reserved for renters in the low to moderate-income range.

Developers balked and Mayor Ed Lee worked with Supervisor Jane Kim on her initial proposal to produce what critics and some other supervisors called a watered-down policy measure that sets goals, but no mandates, and is too weak to make a difference.

Kim, who represents District 6 (including the Tenderloin, Mid-Market and SoMa), which has seen an economic boom and the majority of the city’s development; insists it will lead to specific rules down the road.

“This is part of a longer road that I am personally committed to walking on with a broad commission of stakeholders who care about making San Francisco more affordable,” Kim said.

Supervisors Eric Mar and David Campos voted to put the measure on the ballot, but don’t like it.

“I feel that 33 percent goal set for affordable housing are way, way, way too low,” Mar said.

Campos said it’s not exploration that’s needed, but action instead.

Mayor Lee agreed with developers that mandating that a third of new housing be below market rate would discourage construction. He hailed the compromise as a way to protect against hurdles that would slow or impede progress toward addressing the city’s housing crisis.

He’s set a goal of creating 30,000 housing units by 2020 with half of them being affordable.