A project that will convert Boston’s West End Library into affordable housing is now under review by the Boston Planning & Development Agency. 

A letter of intent for the West End Library Redevelopment Project was submitted by developer Preservation of Affordable Housing and Caste Capital in August. Now, five months later, it’s one step closer to being a reality.

The proposed mixed-use development, located in Boston’s West End at 151 Cambridge St.,“represents a significant step toward addressing the City of Boston’s housing and community resource needs,” according to the project notification form dated Jan. 7.

If approved, the existing library will be replaced with a new, approximately 176,000-square-foot mixed-use building featuring a 12-story residential tower above a new two-story public library. The residences will comprise 119 affordable housing units reserved for households earning below 80% of the area median income.

“The project will provide essential housing opportunities for some of Boston’s lowest-income families in a neighborhood with strong economic potential, close to transit, grocery stores, health care facilities and other essential services,” according to the filing. 

The project’s impact extends beyond housing and also includes a new outdoor plaza located between the nearby Otis House Museum and library to create more open and shared space in the area. 

“The West End Library redevelopment will be a transformative project for the neighborhood of the West End,” the developers said in their filing. “By seamlessly blending affordable housing, public resources and thoughtfully designed spaces, the project will enhance neighborhood connectivity and foster a sense of belonging for all residents, regardless of income or background.”