Part of an ongoing series of posts to support better streets in the City of Sacramento during their 2023 update of Street Design Standards. New standards must be innovative, safe, and equitable, and it will take strong citizen involvement and advocacy to make them so.
Signal cycles will be the shortest timing consistent with ample time for walkers to cross
Shorter crossing distances and therefore shorter signal cycles can be created via lane reductions and curb extensions
Signalized intersections will be evaluated for signal elimination and conversion to stop-controlled intersections
Leading pedestrian intervals (LPI) will be installed at all signalized intersections with pedestrian signals; LPIs will be a minimum of three seconds, longer in high pedestrian crossing areas
All pedestrian activation buttons will be removed, or will be converted to audible-only signal activation. Temporary signing will be installed when a button has been deactivated but not yet removed.
I earlier posted on too many traffic signals? in the central city, which should be eliminated in favor of stop controlled or yield controlled intersections.
I’ve written about existing sidewalk buffers or lack thereof (sidewalk buffer widths), and a solution for areas without sidewalk buffers (street trees in the parking lane), and now on to sidewalk standards. Sidewalk areas are composed of the sidewalk, sidewalk buffer (also called planting strip or furniture zone), and pedestrian scale lighting.
Design criteria:
All new or reconstructed streets will have sidewalks, sidewalk buffers, and pedestrian scale lighting
Reallocated or mitigated streets will have sidewalk buffers added if right-of-way can be reallocated
Sidewalk areas may also include sidewalk-level bicycle facilities
Attached sidewalks (sidewalk adjacent to the curb) will not be used for new or reconstructed streets
Sidewalk width:
Minimum sidewalk width will be six feet in areas of 85% of more residential
Minimum sidewalk width will be eight feet in all other areas
Sidewalks must be completely free of obstructions, encroachments, or driveway aprons into their minimum width
Sidewalks adjacent to and within 1/8 mile of schools will be a minimum of 8 feet; sidewalks used for drop off/pickup will be a minimum of 10 feet
Sidewalk buffer width:
Minimum sidewalk buffer width will be eight feet in order to accommodate a canopy of mature trees; if a lesser width is available, parking areas will be considered for tree placement
Sidewalk buffer may also accommodate street related infrastructure and utilities, street furniture, bike and scooter parking, dining areas, bioswales, and other related uses
Sidewalks will receive priority use of right-of-way; travel and parking lanes, and bike facilities, will be placed in remaining right-of-way
Bus stop amenities will not be placed within the sidewalk minimum width; the sidewalk buffer may serve as clear sidewalk abutting the curb, with appropriate design and transition; transit amenities may also be placed on transit islands away from the sidewalk and sidewalk buffer
Sidewalks will be continuous over driveways and alleys, without interruption of design or materials
Pedestrian scale lighting will be provided along the street length; motor vehicle scale lighting will not be considered sufficient; intersections and crosswalks may be lit with motor vehicle scale lighting
Design diagrams:
Sidewalks of six or eight feet, with sidewalk buffers of at least eight feet
Tree planters or wells in the parking lane or curb extensions
Alley entrances and sidewalk crossings of alleys
Driveway crossings of sidewalk, with design indicating walking priority
Bus stop amenities (benches, shelters, etc.) with a sidewalk area clear of encroachment
Transit island diagram here or in the transit section
Part of an ongoing series of posts to support better streets in the City of Sacramento during their 2023 update of Street Design Standards. New standards must be innovative, safe, and equitable, and it will take strong citizen involvement and advocacy to make them so.
The purpose of designing streets for transit is to actively shift trips away from private motor vehicles and to transit. Most arterial streets in the city should have dedicated bus rapid transit design, and any street with more than one general purpose lane per direction should have a dedicated bus lane, with red paint.
Transit Street Design Guide will be used along with close collaboration with the transit agency to determine optimal and innovative street designs supportive of transit
Dedicated bus lanes will be provided on all 15-minute frequency bus routes on streets over one lane per direction
Light rail will be given exclusive right-of-way on streets with three or more lanes existing; and considered for streets with two or more lanes existing
Bus bays which force buses to pull out of and into traffic will not be used, except where the transit agency has identified the need to wait for a timed stop or to layover
Curb extensions may be lengthened to provide in-lane bus boarding
Dedicated bus lanes shared with bicyclists will be used only when high quality bicycle facilities on an immediately parallel street are not available, or to solve right-of-way issues of one block or less
Bus routes with 15-minute or better frequency, and light rail, will have transit signal priority at all intersections
Design diagrams will be developed in cooperation with the transit agency:
Bus stops, including stop amenities, with preservation of sidewalk passage
Concrete bus pads to lessen pavement deterioration
Bus boarding extensions on streets without bike facilities
Bus boarding islands with bicycle facilities behind, including design features that slow bicyclist traffic behind the island to prioritize walkers
Raised platforms for low floor or level boarding of light rail vehicles
Bus rapid transit streets, including potential raised platforms
Bicycle facilities will be provided within 1/4 mile of every origin/destination
Regular bike lanes (Class 2) may only be used where design and posted speeds are 30 mph or less
Separated bikeways (Class 4) will:
be used for design and posted speeds above 30 mph
have a minimum width of 8 feet, to accommodate passing and wider devices
use hard curb protection where parking protection is not available, or parking utilization is low
Signals
Bicycle signals will be used as necessary to ensure safe crossing of intersections, appropriate priority for bicyclists, and safe transitions to and from separated bikeways
Signals at intersections will detect bicyclists in any lane
Streets that host large volumes of bicyclists in general purpose lanes or bike lanes will have signal timing for a green wave, accommodating bicyclist speeds of 12-15 mph and slowing motor vehicle traffic
Parking
Parking for shared mobility devices will be provided in sufficient quantity on wide sidewalks (over 8 feet) or in the street
On-demand bicycle parking (BikeLink or equivalent) will be provided at locations where bikes are commonly parked for more than two hours
The city will work closely with transit agencies to ensure that bus stops with significant bicycling first mile/last mile have sufficient bike parking
Transit
All bus routes with 30 minute frequency or better will have bus boarding islands with bike lanes or separated bikeways passing behind the island; shared bus/bike lanes will only be used to distances of not more than one block, in order to solve right-of-way issues
Streets that provide long distance travel on with low volume and low speed motor vehicle traffic will be designated as bike boulevards, with appropriate marking, signing, and traffic calming treatment
Shared mobility will be managed and/or owned by the city or transit agency with sufficient control to ensure social and transportation objectives, and stability
Design diagrams will include:
Bike lanes (Class 2)
Separated bikeways (Class 4)
Bike boulevards
Contra-flow and two-way cycletracks, for use where safe bicycle facilities are not
Note: A reader asked how a driver would know whether they are on a street where the design speed is well above the posted speed, or whether they were on a street where the design speed was equal to the posted speed. That is a reasonable question. A safely designed street communicates through design what the intended speed is. However, our traffic engineering profession has trained drivers very well with the expectation that it is safe to exceed the posted speed. There will be a transition period as drivers learn 1) to pay attention to the street and what it signals, not just what the sign says, and 2) that new and reconstructed streets are designed for safety of all users, and therefore the design speed equals the posted speed. But in the meanwhile, drivers will need to know. So, I’ve added a sign below that could be used to signal design = posted, with a red border. The color of the sign itself can’t be changed because in our sign system (MUTCD), white is regulatory.
Part of an ongoing series of posts to support better streets in the City of Sacramento during their 2023 update of Street Design Standards. New standards must be innovative, safe, and equitable, and it will take strong citizen involvement and advocacy to make them so.
Streets are designed for a specific speed limit, which is almost always well above the posted speed limit. The original theory was that designing for higher speeds would protect drivers who drive over the posted speed limit. This is outmoded thinking, for two reasons. One is risk compensation, that most drivers will drive at a speed that feels slightly unsafe, so they are driving just over the design speed. Two is that even if the design speed is safe for drivers, it is not safe for walkers and bicyclists.
The points below are policy, not specifically designs. I have realized that it is not just the design standards that need to be updated, but the policies that determine what design will be used in various context. A lot of city policies are not documented, but reside in the minds of the planners and engineers. Because they are not documented, the public can’t evaluate them and ask for changes.
Design speed = posted speed; a street will never be designed or reconstructed for a higher design speed than the posted speed limit
Design and posted speed limits will be set at a level that ensures safety for all street users including walkers along and crossing the street, and bicyclists
All projects that reconstruct or reallocate a street must consider a reduction in the design and posted speed
Lane widths must match design speeds; lane widths will be limited to 9 or 10 feet except that one lane on truck routes, bus routes with 15 minute or better frequency, or dedicated bus lanes may be 11 feet
Local streets will have a design and posted speed of no more than 20 mph
Streets intended for both local and through traffic may have a design and posted speed of up to 30 mph
Streets will not be designed or posted for 40 mph unless the design reduces intersections, and reduces or eliminates driveways and turning movements
No street in an urbanized area will be designed or posted over 40 mph
People have commented on my series of street design posts, online and Twitter and in person, with many questions about how to fix existing streets. My focus so far has been on new and reconstructed streets. Obviously fixing existing streets is a critical issue, and I’m not wanting to neglect it, but part of my approach is summed up as “don’t build stupid”, in other words, don’t ever again design or construct a single transportation infrastructure that prioritizes motor vehicle traffic over access and safety for walkers and bicyclists. The best time for better design was 50 years ago, the second best time is today. But the City of Sacramento, and most cities and counties and state agencies, are continuing to build things that are hostile to people walking and bicycling. Traffic engineering is a remarkably regressive profession, sticking with what was once thought to work, even though it never did, and even though it is absolutely clear that it does not meet our needs today. Transportation infrastructure is meant to last 30 to 50 years, and may be in place longer than that, so everything we do wrong today will be around for a long time. We won’t ever have the money to fix everything (a lot of our transportation investment is basically money we’ve flushed down the toilet), and the Vision Zero or Safe Systems approach of identifying and fixing the locations with the highest fatality and severe injury crashes is right.
My thinking about street design has four contexts:
Note: Added two photos to the bottom, or integrated parking and trees.
In situations where there isn’t any space for trees along the street, usually where a sidewalk buffer (planting strip) was never provided and where a reconstruction of the street to add sidewalk buffers is not in the budget or possible in the right-of-way, trees can be placed in the parking lane. I am not suggesting here that the entire parking area be replaced with trees, but there some trees and their associated shade for walkers and traffic calming effects could be provided on any street with existing parking.
Portland (PBOT) has a sheet about street tree enhancements, which includes Tree Planting in the Curb Zone:
Tree planting in the curb zone allows for encroaching into the on-street parking zone to increase planting widths. This offers an alternative method for increasing tree well size without negatively impacting people walking.
This new tool provides an opportunity to plant trees along curb tight sidewalks or where the furnishing zone is too narrow for large street trees, locations where tree planting would not be possible under current guidance.
PBOT Pedestrian Design Guide trees in the parking lane
San Francisco has a Parking Lane Planter page:
Parking lane planters are landscaped sidewalk extensions placed between parking spaces at regular intervals or at specific locations. They provide space for street trees and landscaping on streets with narrow sidewalks, where tree planting is limited by conflicts with utilities or driveways, or where there is a desire to visually narrow the roadway.
It does not seem as though most cities have policies about placing trees in the street, and those that do, do not seem of long standing, but certainly the practice exists. Street trees in general, though, are of long standing, with every city having policy and design guidance. Sometimes urban forestry and transportation policies and transportation are well integrated, but as often, not.
The City of Sacramento does have an inventory of trees on city property, which includes planting strips (sidewalk buffers). I don’t know of any trees in the parking lane in Sacramento.
Two readers pointed out locations in Sacramento where parking and street trees are mixed in. Both of these were designed this way; the trees were not added later. Both are on R St, the first with a housing development, with parallel parking, the second with housing and commercial development, with perpendicular parking.
R St between 25th & 26th, south side, parallel parking and treesR St between 16th & 18th, south side, perpendicular parking and trees
The City of Sacramento started a design with protected bikeways on streets with significant bus traffic on P Street and Q Street in downtown Sacramento. I live on P Street, so see use of the bikeway on a daily basis. It works OK. P and Q are not heavily biked streets, and the separated bikeways are not heavily used, but they are OK. And actually, P Street doesn’t work well for buses. Since much of the bus traffic is commuter buses, a lot of them over a short period of time, there is often a stack-up of buses blocking traffic and interfering with each other at a stop opposite me on P Street at 13th Street.
Note: I’m using the term separated bikeway here because it is the term in state law, and therefore planning and engineering documents. Most people call these protected bike lanes, or sometimes cycletracks, though the term cycletrack is more commonly used for two-way bike facilities. Use whatever term you’d like!
On Q Street eastbound, the separated bikeway transitions to a bike lane at 14th Street. Since there are bike lanes on both sides of Q Street to the east, a bicyclist a decide where to transition to the right side of the street. This works OK.
On P Street westbound, however, it is a completely different story. The separated bikeway ends at 9th Street. To the west there are no bicycle facilities of any sort. It is a three lane traffic sewer (what I can three or more lane roadways, the purpose of which is solely to flush traffic in and out of downtown). With the construction going on all through downtown, P Street is and has been reduced to two lanes is several places, and with state workers mostly working from home, there is much less traffic in downtown. Nevertheless, the design is fatally flawed. I use the term ‘fatally’ on purpose – it is a design likely to result in bicyclist fatalities.
Part of an ongoing series of posts to support better streets in the City of Sacramento during their 2023 update of Street Design Standards. New standards must be innovative, safe, and equitable, and it will take strong citizen involvement and advocacy to make them so.
When two local streets intersect, the priority should be for people walking. I’ve created a diagram of what such an intersection might look like, and measure. Notice that the travelway, the area used by moving motor vehicles, is much narrower than is true on most existing streets. This is intentional. Drivers are slowed by their perception that there is a limited space to pass other motor vehicles, or bicyclists for that matter, and limited shy distance from parked cars. Not only does this make the street safer, it also makes it more pleasant for everyone. Drivers traveling any distance will leave these streets in favor of wider/faster streets. Bicyclists can mix with other traffic due to the slow speeds, and do not need a dedicated area. Design and posted speed (if posting is even needed) would be a maximum of 20 mph, and might be less.
Parking is present and welcome, both because it is probably needed, and because it slows motor vehicle traffic. Every corner has a curb extension to shorten the crossing distance for people walking, to increase visibility between walkers and drivers, and to further calm traffic.
Sidewalks of at least six feet, and sidewalk buffers of at least eight feet are included.
Most significantly, sidewalks are raised and extended, with concrete, across the intersection. This enforces the perception that this is a place for walkers, where drivers and motor vehicles are guests. And it is a place where kids could play in the street, as used to be the right of every kid before we let cars dominate our streets. There is still significant pavement for motor vehicles (and bicyclists), but it no longer dominates the neighborhood.
I will address what kinds of streets these are in the future, but what I envision for now is a street with about 80% or more residential, multi-family and single-family. Small businesses on single parcels would be allowed, particularly on corners, but there would be no large commercial or retail, and there would be no surface parking lots.
diagram of intersection of two local streetsRead More »
One of the elements of street design is the width of sidewalk buffers, and how these are presented in design standards. The sidewalk buffer is the area between the curb and the sidewalk. The city calls sidewalk buffers ‘planting strips’, and this is often how they are used, but it is not the only use, and in more urban areas, there are often multiple uses of the sidewalk buffer.
I did a sampling of sidewalk buffer widths in the central city, and a few other parts of Sacramento. I am not claiming any insight into the overall pattern. The city does not have a publicly available database or GIS layer of sidewalk locations and widths, let alone locations and widths of the buffers. I have heard rumors that they are developing one, but I have been hearing that rumor for the last ten years, so I’ve become doubtful.
Typical buffer widths in the central city range from six feet to nine feet, with seven feet being the most common. With huge mature trees, the narrower buffers are too narrow of the trees, and the sidewalks have had to be modified. The photo below shows an example, and these situations are everywhere.
sidewalk narrowed for tree roots, Q St near 14th StRead More »
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