12.14.23 CC Amend Zoning 10.3 Vegetated Roofs — File 23-0791

CITY OF SOMERVILLE ORDINANCE NO. 2023- IN CITY COUNCIL: ________, 2023 Be it ordained by the City Council, in session assembled, that chapter 10 of the Zoning Ordinance of the City of Somerville is amended as follows by deleting the struckthrough text and adding the underlined text. Approved: President Approved: Mayor

Somerville Zoning Ordinance Date Printed: 7/12/2023 1 i. Preexisting, substantially equivalent vegetation that is preserved within the landscape buffer may substitute for any required landscape buffer plantings provided that the preexisting vegetation is healthy and growing. ii. Water, sanitary sewer, electrical, telephone, natural gas, cable, storm drainage, or other service lines are permitted within landscape buffers. iii. Surface parking is prohibited within a required landscape buffer. 10.3.7 Parking Lot Landscaping a. General i. The landscape standards of this section take precedence over parking standards found elsewhere in this Ordinance. b. Perimeter Planting i. Surface parking must be screened from view along any lot line abutting a public thoroughfare, excluding an alley, by a landscape buffer designed in accordance with §10.3.6 Landscape Buffers. c. Landscape Islands i. A landscape island must be provided every five (5) parking spaces and at the end of every row of parking spaces. ii. Landscape islands may be consolidated and intervals may be adjusted as necessary to preserve existing trees or facilitate storm water management. iii. Landscape islands abutting a single row of parking spaces must be at least eight (8) feet in width and the same length as the parking spaces. Each island must include one (1) large tree. iv. Landscape islands abutting a double row of parking spaces must be at least eight (8) feet in width and the same length as the parking spaces. Each island must include two (2) large trees. 10.3.8 Vegetated Roofs a. Construction of a new principal building or the substantial renovation of an existing principal building with a flat roof in the Mid-Rise, High-Rise, Assembly Square Mixed-Use, or Commercial zoning districts, except development subject to the Affordable Housing overlay district, must include a vegetated roof for eighty percent (80%) of the available roof area. i. Roof area for roof mounted cellular, radio, and internet transmission equipment; vents or exhausts; solar systems, including photovoltaic devices; any equipment required to support the operation of the building; and path of travel to access rooftop equipment is exempt. ii. Balconies and roof area for outdoor amenity space and required open space are exempt. iii. Non-habitable architectural features, required screening, and unobstructed areas required by the Massachusetts State Building Code are exempt.

Somerville Zoning Ordinance Date Printed: 7/12/2023 1 ii. Each additional bonus may have a multiplier up to one-tenth (0.1) for each bonus. Table 10.4.1 Green Score Calculation Credit Multiplier Soils Landscaped area with a soil depth < 24 inches actual sf 0.3 Landscaped area with a soil depth => 24 inches actual sf 0.6 Pervious Paving with 6 to 24 inches of subsurface soil or gravel actual sf 0.2 Pervious Paving with more than 24 inches of subsurface soil or gravel actual sf 0.5 Groundcovers Turfgrass, mulch, and inorganic surfacing materials actual sf 0.1 Plants Vegetation less than two (2) feet tall at maturity actual sf 0.2 Vegetation at least two (2) feet tall at maturity 12 sf/plant 0.3 Trees Small tree 50 sf/tree 0.6 Large tree 450 sf/tree 0.6 Preserved Tree 65 sf/tree 0.8 Engineered Landscape Vegetated Wall actual sf 0.1 Rain gardens, bioswales, and storm water planters. actual sf 1.0 Green Vegetated Roof with up to 6” of growth medium (under solar systems) actual sf 0.1 (0.3) Green Vegetated Roof with 6”-10” of growth medium (under solar systems) actual sf 0.4 (0.6) Green Vegetated Roof of 10”-24” growth medium (under solar systems) actual sf 0.6 (0.8) Green Vegetated Roof of over 24” growth medium – per individual landscape elements 10.4.6 Eligibility a. All landscape elements must meet eligibility and quality standards established by the Director of Public Space and Urban Forestry to ensure the long-term health, viability, and coverage of plantings. 10.4.7 Measurement a. If multiple landscape elements identified in the first column of Table 10.4.1 occupy the same area, for example groundcover under a tree, the full square footage or equivalent square footage of each element is counted. b. For trees, large shrubs, and large perennials, use the equivalent square footage indicated on Table 10.4.1.