Tag: design speed

SacCity design speed

Dan AllisonLeave a comment

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

Freeport Blvd as a failure of vision and possibility

Dan Allison5 Comments

Another post on the Freeport Blvd Transportation Plan. See the category Freeport Blvd for other posts.

It should be obvious, if you have been reading, that the City of Sacramento’s Freeport Blvd Transportation Plan is a failure of vision and possibility. How so?

The city removes from all planning efforts the possibility of reducing speed limits on streets that are reconstructed, usually complete streets projects. Whatever the speed limit is before the project will be the speed limit after the project. I’ve written about this before: lower speed limits on complete streets in Sac. I get that changing posted speed limits without changing roadway design has only limited effect in lowering speeds. But we are talking about reconstructing streets, the very design changes that are necessary to effectively lower motor vehicle speeds. Yet the city refuses to consider lowering speed limits when planning reconstructed roadways. Posted speed is like a rachet, it can only increase but never decrease. Some planners and engineers go so far as to claim that the law prevents lowering of speed limits on reconstructed streets. That is a lie.

The city also refuses to consider lane reductions (also called road diets, roadway reallocation, or right-sizing) when average daily traffic counts (ADT) are above certain thresholds. It will not consider that ADT is above what it should be because the city earlier widened roadways and induced the travel that is now resulting in high ADT. Again, lane counts are like a rachet that goes only one direction. You can increase lanes, but you can’t decrease lanes, except in situations where the roadway is so obviously overbuilt that it would be ridiculous to suggest maintaining that number of lanes.

The city has a responsibility to reduce vehicle miles traveled (VMT) in the city, under state law, under SACOG guidance, and its own policy in the Mayor Climate Change Commission Report and Climate Emergency declaration. Yet in transportation planning, the city seems to be fully committed to maintaining the current levels of VMT by ensuring that the current levels of traffic are not reduced. This is climate arson.

Community input to the Freeport Blvd planning process provided high priorities: safety, economic vitality, and walkability. Yet the plan maintains motor vehicle capacity, ensuring that the community priorities will be only partially met. This is not a compromise between drivers and walkers and bicyclists. It is throwing crumbs to the walkers and bicyclists so that drivers may eat nearly the entire cake.

Freeport Blvd, today, is a suburban form. Uninviting streets, hostile walking and bicycling, many small businesses in strip malls and a few big box stores (some of them closed or failing). The built environment is an artifact of the time and way in which Sacramento grew in this direction. It is a fact. But the city, in its transportation plan, makes no effort to change or mitigate that fact. In no way does it even suggest transformation to a more vibrant and interesting place. At the simplest level, it just adds bike lanes and changes nothing else. I’m not against bike lanes, and certainly not against separated (protected) bikeways, but they are not transformative. What would be transformative is shifting Freeport towards a walking-first transportation corridor, a destination for people who live there and people who travel to there.

The city intends to add a number of new crosswalks to the corridor. That is good news, as distances between safe crossings are too great. The problem is, most of these will require extensive signalization to protect the people crossing there, because speed limits are such that a person hit by a motor vehicle will be seriously injured or killed. Lower speed limits, not just posted but enforced by design, would allow much less expensive crossings. Money matters. The city will put very little of its own funds toward these changes, depending mostly on regional, state and federal funds, which will always be too little and too slow.

This plan is only the first step in changing the roadway. Grants will be solicited for major project work. A few critical locations will be improved in the near term. But the plan as a whole is decades away from completion, particularly if the probably unnecessary section south of 35th St is included. The city has done pretty well obtaining grants for complete streets, but with an entire city full of streets needing improvement, Freeport Blvd can’t be and won’t be the only priority. Once the plan projects are complete, the street won’t likely be changed for 30 years. So 50 years from now, more or less, the roadway will look like what the city has planned today. Will it meet the needs of citizens at that time? Very, very unlikely. In the future, VMT will be and must be much lower than it is now. A much higher percentage of trips will be made by walking and bicycling. The built environment will densify, with more small businesses, though some stretches won’t make it and will fail. That’s OK. Properties with failed businesses are good candidates for infill housing, which will support those businesses remaining. But housing along a dangerous traffic sewer, as Freeport Blvd currently is and will largely remain under the city plan, is a disservice to everyone who lives there. Who wants to live on a busy arterials stroad, where you can’t let your kids outside because the risk of traffic violence is too great, and the air hazardous to breathe, and the noise of traffic is a constant psychological and health danger? Riding to the grocery store may be slightly more pleasant and somewhat more safe, but many people still won’t want to because they aren’t comfortable with regular bike lanes beside high speed traffic, and complicated intersections. People won’t want to walk during the summer because the city failed to plan for and install trees along the sidewalks.

Enough said for now. I may write some more or post others if people point out important issues that I have not addressed. Otherwise, the next post will be just before the plan goes to city council, in hopes that citizens will urge the council to reject this plan as too flawed for use. I was very disappointed that the City of Sacramento Active Transportation Commission rubber-stamped the plan and passed it along to council, but that is water under the bridge.

The city can do better, but only if a significant number of citizens press their council members to set a higher standard for transportation planning than is exhibited in the final draft plan.

(in)complete streets

Dan Allison1 Comment

Note: This is a follow-on to streets – stroads – roads. It will make more sense if you read that one first.

The complete streets concept says that all modes of travel (walking, bicycling, motor vehicles, and transit when appropriate) should be accommodated on streets. The accommodation is accomplished by providing separate spaces for each: sidewalks for people walking, bike lanes for people bicycling, general purpose lanes for people driving.

The concept was and is promoted by the National Complete Street Coalition, now part of Smart Growth America, since 2004. The traffic planning and engineering professions strongly resisted the concept for years, but it now receives at least voice support from most planners and engineers. In California, chances of getting a transportation infrastructure grant are low if it does not at least claim to meet complete streets concepts.

The two biggest weaknesses of the complete streets concept are:

  • No guidelines for the frequency of safe crossings are built into the complete streets concept. It could be, but it is not. So travel along corridors is better, but crossing that corridor may not be any better than it was before.
  • Speed limits are rarely reduced on a reconstructed complete streets. Traffic lanes are often narrowed, and sometimes reduced, in an effort to slow traffic. However, a design that actually enforces a lower speed, and therefore allows a lower speed limit is rarely considered.

FHWA (Federal Highway Administration) recent released a Complete Streets Report to Congress and related webpage. I have not had a chance to look at this in detail, so I don’t know if the federal concept overcomes the weaknesses of the previous complete streets concept. The graphic below was the leading one in the new effort, and was justifiably criticised as presenting an unattractive if sort-of compliant complete street, but some people who have read the document say it is better than this. Streetsblog USA: USDOT Tackles Overlooked Barriers to ‘Complete Streets’ — And Sparks Debate.

FHWA complete streets graphic

Caltrans has a recently adopted Complete Streets Policy. The City of Sacramento has a complete streets policy. Citrus Heights, Elk Grove, Folsom, Rancho Cordova, and the county express support for complete streets concepts in their general plans, and have complete streets projects, but apparently do not have specific policies.

There have been a number of complete streets project already in the Sacramento region, and more are on the way. The proposed Measure 2022 transportation sales tax flags complete streets for much of investment, so it is important to understand what a complete street is and is not. Let me say that a complete street is almost always better than what was there before. A lot of our streets were constructed without sidewalks, or with narrow sidewalks interrupted with utility poles and other obstructions, and lacking curb ramps. Complete streets usually have continuous sidewalks of six feet or more, with fewer (but not no) obstructions, and curb ramps at corners. Almost all of our streets were constructed without any place for bicyclists, so a complete street with bike lanes may be an improvement (though many traffic engineers continue to think that painted bike lanes work on higher speed streets).

I was working partly in the City of Citrus Heights when the Auburn Blvd Complete Streets Phase 1 project was designed and implemented. Indeed, travel along the corridor was much improved, and the road was more welcoming to all modes of travel. But there were no more safe crossings of Auburn Blvd than there were before. The crosswalks were still way to far apart for people to conveniently access the businesses, homes, and schools along the corridor. The speed limit was unchanged, though my perception was that actual speeds were a bit slower.

Nearly all streets that have become, or are proposed to become, complete streets are stroads. Think of a major roadway in the county, and you are picturing a stroad. Making a stroad a complete street does not make it not a stroad. Complete streets projects often forget to answer the most basic questions: what is the purpose of this roadway, and how can we construct it so that it fulfills that purpose? A stroad with sidewalks and bike lanes is still a stroad if the primary function is to move people along the corridor, rather than allow them to be in the corridor.

If the purpose of a roadway is to move a high volume of motor vehicles quickly, a road, then sidewalks and bike lanes probably aren’t appropriate, and those modes should be provided for on parallel routes. If the purpose of a roadway is to provide a place for people and building wealth, a street, then sidewalks and SLOW or no motor vehicle traffic is the only appropriate design. This is often expressed as a place where ‘cars are guests’ and bicyclists mix in with other street users rather than needing an exclusive space.

Yes, I am talking about an ideal here. Almost all of our roadways were designed and function inappropriately. We have a long ways to go, but we at least have to get started by stopping what we are doing wrong, and starting to do it right. The proposed Measure 2022 transportation sales tax largely commits to continue doing it wrong, for 40 years. That is the next post.

Yes, and lower speed limits

Dan Allison1 Comment

I believe that stroads should be turned back into Streets, and roads preserved for their transportation function. I’m a Strong Towns member, and fully support the argument that the best solution to stroads is to reconstruct them into streets. #SlowTheCars is the right approach. Key to that approach is that changing speed limits doesn’t do much to slow cars, and that ticketing people for going the design speed instead of the posted speed is often just a pretext for profiling and oppression.

BUT. It will be a long while and trillions of dollars to accomplish that. Undoing the damage of the past is not easy, because the money it would take to fix everything has long since gone into the pockets of those who profited from unsustainable (socially, economically, environmentally) development. We will have to triage, changing the most dangerous places first, and those places with the best chance of becoming walkable, livable, and vibrant second. We may never, and perhaps should never, get to those places that are the model of the suburban experiment. Many suburban places will fail and go back to agriculture. Others will not. But spending a lot of money to fix a suburban stroad, adding sidewalks and bike lanes and street furniture, will be good money after bad because these places won’t ever be dense enough or successful enough to pay back the investment.

Back to speed. It will be a long while before we can lower the design speed of stroads and streets back to the correct speed. In most cases, that design speed should be 20 mph. Occasionally higher or lower, but mostly 20. In the interim, I think that we should reduce the speed of all urban streets, that are not arterials and collectors, to 20 mph. I am not suggested that this limit be tightly enforced, as the point is not enforcement but education and commitment. A community willing to lower the speed limit to 20 is a community willing to think about safety and livability, and to accept that the way we have done thing in the past is absolutely not what we need in the present or future. Setting speed limits to 20 is a message to pay attention and think about consequences. Portland and Seattle have recently reduced some speed limits to 20.

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