Watch the following YouTube videos from the October 6 launch event at Metro Headquarters for helpful information about the Model Design Manual for Living Streets:
- Suzanne Bogert
- Bill Roschen
- Ryan Snyder
- Madeline Brozen
On November 8, 2011, the Ryan Snyder and Madeline Brozen presented to members of the US DOT livability about the Manual. The presentation is available here.
Why is the document called a manual?
This manual provides principles of good design, as well as a significant number of concept drawings. In many instances, it provides the design concepts that can be used to create construction documents from. In some areas it provides more detail than many existing manuals. For example, it spells out significant detail about sidewalk cross sections along different types of streets in different neighborhoods. It stays away from the rigid standards that often only apply to abstract situations. Other street manuals have more detailed engineering guidance and are endorsed by a federal or state agency. However, this manual has some specific designs but moreso what is important is that this manual address what to build when thining about creating living streets.
How does this manual comply/address fire code concerns?
The California Fire Code can impede street design in limited circumstances. The state legislature has adopted the National Fire Code. The National Fire Code is written by a private agency and has no official legal standing unless states or municipalities adopt it, as has been done in California. The primary barrier caused by this adoption is the requirement for a minimum of 20 feet of an unobstructed clear path on streets. To comply with this, streets with on-street parking on both sides must be at least 34 feet wide. This prevents municipalities from designing skinny and yield streets to slow cars and to make the streets safer, less land consumptive and more hospitable to pedestrians and bicyclists.e are ways around this requirement. If the local jurisdiction takes measures such as installing sprinklers and adding extra fire hydrants, or the adjacent buildings are built with fire retardant materials, it may be able to get the local fire department to agree to the exception. Additionally, the California state Fire Code does exist in conflict with properly researched guidelines and standards documented by the Institute of Transportation Engineers and AASHTO. Regardless, the authors understand that as part of the process of re-thinking street design, it is important that planners and engineers work with their local fire department early in the process of updating their standards.
What is the legal standing of this document?
To clarify, cities are authorized to adopt or modify their own practices, standards, and guidelines that may reflect differences from the Green Book and the HDM. If these changes generally fall within the range of acceptable practice allowed by nationally recognized design standards, the adopting agencies are protected from liability to the same extent they would be if they applied the Green Book or the HDM. Most changes to streets discussed in this manual fall within the range of the guidelines or recommended practices of nationally recognized organizations such as AASHTO, ITE, Urban Land Institute (ULI), and Congress for the New Urbanism (CNU).Unless otherwise noted, everything in this manual can readily be adopted and incorporated without fear of increased liability. In addition, this manual carries the credibility of the many top-level experts who produced it. In some cases, AASHTO design guidelines may not provide information on innovative or experimental treatments that have shown great promise in early experiments and applications. Since AASHTO is a design guide, agencies have some flexibility to use designs that fall outside the boundaries of the AASHTO guide. Deviation from the range of designs provided in the AASHTO guide requires agencies to use greater care and diligence to document their justification, precautions, and determination to deviate from the guidelines. In California, the precautions to establish design immunity should be followed. These include consideration/analysis and approval by a registered engineer qualified to sign the plans, and certification by the city council or reviewing body clearly indicating the intent of the agency. This process documents the engineering judgment that went into the design. Additionally, it is important to note that not all the treatments in this manual fall within the category of traffic control devices. For example, traffic calming treatments are not traffic control devices and as such the state exercises no jurisdiction over them.
More questions may be posted here in the future.