Latest Updates
The City has completed the Green Street and Sidewalk Stormwater Design Guidelines, which is an update to the City's 2014 Green Sidewalks BMP Design Guidelines. The update aligns the typical details with current Virginia Stormwater Management Standards and Specifications and changes to City policies and procedures, and also includes additional options for structural stormwater best management practice (BMP) development in the street and sidewalk right-of-way.
The update process has been guided by a Work Group formed in January 2018 and representing the Department of Transportation & Environmental Services, including Development and Right-of-Way Services, Stormwater Management, Transportation Planning, and Public Works Services, as well as the Departments of Planning and Zoning, Public Implementation, and Recreation, Parks & Cultural Activities. The update aligns with current Virginia Stormwater Management Program Regulations, standards, and specifications, and also aligns the design guidelines with City standards, policies, and plans approved since 2014 when the guidelines were first created.
Presentations
- Outreach to NAIOP – September 16, 2020
- Environmental Policy Commission – November 16, 2020
For additional information, contact Melanie Mason at melanie.mason@alexandriava.gov or 703.746.4132.
Applicability
These guidelines are applicable where development will include the construction of new roads and sidewalks, or significant rehabilitation of the existing right-of-way.
Typical Stormwater Details for Streets & Sidewalks
These details show typical configurations, rather than required standard configurations. This distinction is deliberate, as the City recognizes that to create streetscapes that are beautiful, functional, and contextual, designers must use their own creative thinking and professional judgment as well as considering site constraints. The 2020 Design Guidelines and the typical drawing designer notes emphasize areas where the designer must exercise professional judgment to respond to the site.
The typical details are supported by the design guidelines, which reflect City design preferences and City character. Details required for an individual project may vary depending on the type of project and site conditions. Any BMP in the right-of-way may be subject to approval by the Director of Transportation & Environmental Services or his/her designee when the ultimate maintenance responsibilities are assumed by the City.
For use on construction documents, design professionals must modify facility plan and section configurations, materials, and construction notes to address the project’s site conditions and meet project performance goals. To ensure that your use of the details is site-specific, please:
- Adjust plans, sections, and construction notes for site-specific design
- Remove the title block from the details used in your set and replace it with a title that aligns with your projects’ construction document nomenclature
- Incorporate all detail call-outs and references into the construction documents so that the contractor will have all the information required to build the project
Right-of-Way BMP Plant Lists
This list is not intended to be all-inclusive. Selected plants for Bioretention BMPs in the right-of-way are intended to offer a variety of types, sizes and offering seasonal interest and are compatible with the species identified in many of the City’s design guidelines for specific areas. In addition, they have been carefully chosen as the best examples of plant species capable of providing vigorous performance both within a local urban context and in the specific conditions demanded by BMPs as required by the BMP Clearinghouse specifications.
Refer to the Landscape Guidelines for more information on Alexandria Natives and for Invasive Plant Lists. Invasive plants are prohibited from use.
Tree Planting Notes
For bioretention BMPs with trees, the following notes shall be provided on plan submissions:
- Expose root flare and plant tree with root flare at grade.
- All excess soil and dug material above grade shall be removed and disposed of by the contractor.
- Remove and dispose of top 50% of wire and burlap or 100% of fabric bags.
- Spread a 3” layer of mulch 36” out from the trunk in all directions. Mulch shall be kept 6” from the trunk itself.
- Compact media beneath root ball such that rootball does not sink.
- Thoroughly water in tree with no less than fifteen (15) gallons of water to settle the soil around the roots of the root ball at the time of planting; Watering shall be completed regardless of the weather at the time of planting
Reference Standards
Stormwater BMPs in the ROW must comply with the most current versions of the Reference standards.
- Virginia Stormwater BMP Clearinghouse standards and specifications.
- Design and Construction Standards 1989
City Plans and Standards
The Green Sidewalk BMP Design Guidelines work in conjunction with existing City plans, policies, standards, and guidelines. Links to specific documents are listed below.