Task 1 Typical Street Cross Sections and Intersection Details and Diagrams The design standards and required improvements for subdivisions have been updated in the recent Subdivision Regulations update, Article X Design Principles and Standards and Article XI Required Improvements for Subdivisions and Developments with More than One Building for Dwelling Purposes. Task 1 seeks new plan drawings for typical street cross sections, pavement details, alternative turnarounds, and intersection details that reflect the updated design standards. Separate drawings shall be provided for Type I and Type II subdivisions. Roadway standards in the revised Subdivision Regulations may be viewed online here: https://www.southhadley.org/1318/ProposedDraft-Bylaws A. Typical Street Cross Sections shall include Type I and II subdivision roadways and be based on the standards in Article X Design Standards and shall include: • Right of way and roadway widths • Roadway grades • Horizontal alignment • Intersection details • Sidewalks • ROW tree planting requirements • Grass strips/stormwater green infrastructure • ROW street lighting requirements • Allowed placement for utilities B. Pavement details shall include cross-section diagrams for Type I and II subdivision roadways based on the standards in Article XI Required Improvements. C. Alternative turnaround diagrams shall include plan diagrams for Type I and II subdivision roadways based on the standards in Article X Design Standards, and include cul-de-sac and deadend streets, “Y” and “T” configurations. D. Alternative intersection diagrams shall include standards for horizontal curves and required offsets for opposing streets. Task 2 Recommended Tree and Shrub Planting Guide There are several excellent guidebooks in circulation. This task may draw upon existing resources publicly available, provide reference to them, and provide additional information and standards specific to South Hadley. The guidebook is to include a list of recommended tree and shrub species including species details, planting guidelines, and sustainable design standards for landscapes. Such standards are anticipated to include, at a minimum, shall include: • 10-20-30 Rule for Tree Diversity be applied to new developments such that plantings are comprised of no more than 10% of any one species, 20% of any one genus, or 30% of any family. • Plantings be comprised of at least 70% native species, preferably native to New England but also native to other nearby North American eco-regions as appropriate due to climate change. • No invasive species, with reference to the most up-to-date edition of the MDAR Prohibited Plant List. No plants from this list shall be bought, sold, or transplanted into any landscaping.
