Planning Board approves shared bike parking for Kendall Square redevelopment; reviews plaza design and sets PB 3‑15 deadline

CAMBRIDGE, Mass. — The Cambridge Planning Board on Aug. 19 voted to allow Boston Properties to share long‑term bicycle parking between the Proto residential building at 88 Ames Street and the adjacent 325 Main Street office building, designated the change as a minor amendment to the MXD infill development concept plan (PB 3‑15), reviewed updated design plans for the center plaza and East‑West connector, and granted the applicant an extension to complete work on a separate major amendment to PB 3‑15.

The board granted the parking amendment unanimously, 6‑0, after hearing staff presentations and a proponent briefing. The changes will let the applicant count and use some of the 150 long‑term bicycle spaces located in a three‑level “bike shed” at 88 Ames (part of the Proto residential project) for employees and short‑term users at 325 Main, while keeping 113 Level‑5 spaces reserved for Proto residents. The board also voted that the requested changes to PB 3‑15 qualify as a minor amendment and approved a separate extension of the major amendment review period to Dec. 31, 2025.

Why it matters: The decision reallocates underused residential bike parking to meet rising demand at 325 Main — an outcome proponents called a way to better match supply and demand in Kendall Square without new construction — and advances the planning review for the larger Boston Properties MXD redevelopment, including the public plaza to be built above an electrical substation.

What the board approved and the vote details

- Shared bike parking and short‑term parking allocation (PB 2‑94 / amendment to PB 3‑15): The Planning Board voted to grant the requested special‑permit amendments, adopting conditions recommended in Community Development Department (CDD) memos. Motion to grant moved by Carolyn Zurn, seconded by Dan Anderson. Roll‑call: Mary Liedecker — yes; Ashley Tan — yes; Carolyn Zurn — yes; Dan Anderson — yes; Joy Jackson — yes; H. Theodore (Ted) Cohen — yes. Outcome: approved (6–0).

- Minor‑amendment determination for PB 3‑15 (325 Main Street): The board unanimously determined the proposed changes to PB 3‑15 constituted a minor amendment that can be approved by a written determination. Motion moved by Mary Liedecker; seconded by Ashley Tan. Vote: 6–0.

- Extension of time for the separate major amendment to PB 3‑15: The applicant requested an extension for the pending major amendment (a land‑use reallocation among sites in the MXD plan); the board approved an extension of the review and decision period to Dec. 31, 2025. Motion moved by Carolyn Zurn; seconded by Ashley Tan. Vote: 6–0.

What the amendment changes, in detail

- Existing and proposed counts: The Proto residential building (88 Ames Street) was built with 295 long‑term bicycle spaces: 113 on a Fifth Level directly connected to the building (reserved for residents) and 150 spaces in a three‑level detached bike shed (54 ground, 48 second, 48 third). An additional 42 short‑term racks exist on Ames Street. Under the approved amendment, the 113 Level‑5 spaces remain exclusively for Proto residents; the three‑level bike shed’s 150 spaces will be shared between Proto residents and 325 Main users, and the bike shed ground floor will include 47 short‑term spaces serving 325 Main and the public. The applicant said the bike shed entrance is within roughly 50 feet of 325 Main’s main entrance.

- Rationale presented: Applicant representatives said 88 Ames’s bike shed has shown persistently low utilization through several years of operation (peak observed usage around 48 bikes, about 18% of the 295 long‑term spaces), while 325 Main — occupied by a tech tenant — has had increasing employee demand for bicycle parking. CDD and the Cambridge Department of Transportation reviewed the data and recommended conditions; the Planning Board’s findings referenced conformity with the purposes of the zoning sections cited in staff memos and the project review special‑permit criteria.

Design update: center plaza, East‑West connector and playground options

After the permitting votes the board heard a design update on PB 3‑15’s public open space components: the Center Plaza (to sit above an electrical substation) and the East‑West connector, both parts of the MXD infill plan for Kendall Square. The proponent (Boston Properties) and design team (Sasaki landscape architects; MBBJ and Stantec architects) presented 50%–100% design development work and two playground concepts for the plaza’s children’s play area — described by the team as the “bird’s nest” and the “beehive.”

- Playground concepts: The “bird’s nest” concept uses timber towers, leaf‑shaped climbing elements and bird‑themed panels and didactic signage; the “beehive” scheme emphasizes hexagonal forms, net climbs and bee‑inspired colors and panels. The team said both options include zones for 2–5 and 5–12 age groups, accessible circulation and educational panels that could interpret the site’s infrastructure.

- Board and CRA feedback: Planning Board members and Cambridge Redevelopment Authority (CRA) staff praised plants and revised pathways, but urged further work on the playground’s scale, materials, color and identity so the play area reads at the same scale as the plaza’s large intake/exhaust architecture and the below‑grade substation. Comments included: - Consider taller/more sculptural play elements and stronger color accents so the play area is legible against large mechanical structures. - Increase planting variety and tree massing where feasible (subject to substation constraints) and clarify seasonal appearance. - Provide clearer pedestrian and bicycle circulation cues on the East‑West connector and coordinate furnishings (benches, lighting) with the plaza palette. - Explore combining structures or linking elements (bridges, nets) to create more continuous play experiences and interior nooks within the play fall zones.

CRA staff and CDD asked the design team to continue refining the playground identity, furnishing plans to support adjacent retail activation, and lighting and plant palettes. The Planning Board voted to conclude the design update and to continue design review as the team advances construction documents; that procedural motion passed 6–0.

Constraints and limits noted

The team and staff reiterated technical constraints tied to the substation and utilities: trees and open water features on the substation roof are limited or prohibited, and some equipment or planting locations are constrained by Eversource and substation access requirements. The design team also said certain temporary planting strategies were used where future development may require relocation.

What happens next

CDD and CRA staff will continue working with the applicant and design team on details requested by the boards — playground identity, planting palette, furnishings and lighting — as construction‑document drawings advance. The major amendment to PB 3‑15 (a separate land‑use revision) remains an open file; the applicant’s requested extension runs to Dec. 31, 2025.

Speakers and attribution

Quoted or attributed remarks in this story come from participants at the Aug. 19 joint Planning Board / CRA meeting: H. Theodore (Ted) Cohen (acting chair, Cambridge Planning Board); Jeff Roberts (Community Development, director of zoning and development); Jeff Lohmberg (Boston Properties representative); Tom Evans (executive director, Cambridge Redevelopment Authority); Dan Anderson (Planning Board, associate member); Mary Liedecker, Ashley Tan, Carolyn Zurn, Joy Jackson (Planning Board members); Eric Thorkelson (CDD, urban design); Cecilia Cobb and Alex Levering (CRA staff); and designers from Sasaki, MBBJ and Stantec who presented the plaza and connector updates. The applicant representative said at the start of the public hearing, “yes, we are, we are okay proceeding with the 6 planning board members,” when asked if the proponent agreed to proceed with the reduced membership.

Ending note

Planning Board approval of the bike‑parking amendment moves a practical, non‑construction change forward that the applicant and staff said responds to observed usage patterns; the more subjective design decisions for the plaza and playground will return to staff and the design review process for further refinement before construction documents are finalized.