Coronado Neighborhood Association

Traffic 101
From the October 2004 Dispatch.

Traffic is a part of our everyday lives. We've grown up with it, so we hardly notice it. Hardly, that is, until it can't be ignored--the sound of squealing tires in the night, a traffic jam that makes us late for work, a stream of cars that makes us worry about the children playing in the front yard. For good or bad, traffic affects the quality of our lives.

In a survey sent to Coronado residents by the City of Phoenix Neighborhood Services Department in the fall of 2003, we told the City that speeding was the number one problem in our neighborhood. Cut-through traffic also ranked high. And residents identified both speeding and cut-through traffic problems as "worsening over time." More so, in fact, than any other perceived problems (including, thankfully, crime and drugs. Years of neighborhood efforts to fight those problems are paying off.)

Our streets can be a beautiful part of our historic neighborhood if we come up with creative solutions to traffic issues. A Fight Back grant from the City of Phoenix is bringing Coronado residents and City departments together to do just that.

Problems defined

Traffic flows like water, according to the traffic engineers. Drivers seek the path of least resistance. And so, when traffic flows sluggishly on arterial streets (like westbound McDowell at 3pm when Summit School students are strolling through the intersection at 7th blocking right hand turns, essentially turning westbound McDowell into a one lane through street), cars turn north into the neighborhood on 10th or Dayton (or even 12th if it backs up far enough) to continue flowing freely. This is called cut-through traffic, and it is a problem at morning and afternoon rush hours. The reverse lane on 7th Street also encourages cut-through on our neighborhood streets by restricting left-hand turns at major intersections during rush hours.

Speeding is a different problem. Speeding happens when the drivers (or water) are unrestricted. This is a major complaint on 12th, a wide street unimpeded by stop signs, which can tempt heavy-footed drivers to speed in off-peak times and young North High drivers to prove their bravado at any time of day.

The traffic reality

Coronado is bounded by two freeways. I-10 delivers high-speed traffic to our neighborhood via off-ramps at 7th and 16th Streets; SR-51 at McDowell and Thomas. We are also bounded by several busy arterial streets (7th Street with reverse lane restrictions at rush hours, McDowell, Thomas and 16th) that move traffic in and out of a growing downtown. If all goes as planned, downtown will thrive with residents living in lofts, stadium attendees, civic center visitors, etc, etc. The number of people using these streets will continue to increase over time, even with a light rail system to carry some of them around.

Traffic solutions are not quick and easy. They require working with the City on traffic studies, identifying appropriate solutions, and reaching agreement among those of us who live here. They are limited by physical conditions at specific locations (like drainage issues, for example), by cost, and by "warrants" from the City (i.e, Is a change warranted by high volumes, pedestrians, accident statistics, etc.?).

But solutions are possible if we begin to work toward them now. And if we address them creatively, our traffic solutions can add to the quality of life and the historic character of our neighborhood.

Streets defined

There are two types of streets in the neighborhood: neighborhood streets which provide direct access to residences and allow for local traffic movements at 25mph, and collector streets. As the name implies, collector streets collect and deliver traffic from neighborhood streets to arterial streets, moving traffic through the neighborhood at 30 or 35 mph, with generally few stop signs. 12th Street from McDowell to Thomas, and Oak Street from 7th Street to 12th are collectors. (Virginia and Palm Lane are not collector streets, although they look and act like collectors between 7th Street and 12th.)

The major streets that surround the neighborhood (like 7th Street) are arterial streets, carrying huge numbers of cars in multiple lanes at higher speeds. Like spring runoff in the mountains, neighborhood streets trickle traffic to the collectors; collectors carry traffic to the arterials; and the arterials flow traffic through the city to other arterials or deliver it to the raging rush of the freeways.

Possible Solutions

Traffic calming can result from enhanced police enforcement or from physical measures. In general (and this is an oversimplified explanation of a complex issue), several options are available to mitigate traffic on neighborhood streets. Collector streets are much harder to change. Why? Because if a collector street carries large volumes of traffic through and out of the neighborhood, it is doing exactly what is was designed to do.

Some possible solutions:

ü Striping.

Adding bike lanes or parking spaces along wide streets can help to visually narrow the width of the street. "Slow" or "30MPH" messages can be painted on the road surface to remind drivers to drive cautiously. (Striping changes are possible on collectors.)

ü Speed humps.

The city loves these because they are quick, easy, inexpensive "fixes." And sometimes they may even be the correct solution for a street. But in general, they just create "turbulence in the water," addressing a problem in one very specific location by moving it to the neighbors' street. Read all about the pros and cons of speed humps at: http://phoenix.gov/STREETS/speedhmp.html.

ü 4-way stop signs.

We have one at Virginia and 12th Street that seems to work just fine. But adding a 4-way stop elsewhere needs to meet 4 criteria,

Both intersecting streets must carry equal amount of traffic,

Pedestrian traffic must be present,

The intersection must present visual impairments (such as walls or trees), and

Collision statistics must support the request.

ü Street closures.

Great examples, if you haven't already seen them, are the many street closures along 1st Avenue from McDowell to Thomas in the Willo neighborhood. Closing a street stops cut-through traffic completely. But it is very expensive, it is dependent on high traffic counts, and it needs the support of both residents in the immediate area and City traffic engineers.

ü Diverters.

There are several kinds of diverters: chicanes, center islands, diagonal diverters, forced turn islands, etc. A great example of a diagonal diverter can be seen in the Windsor Square neighborhood at 2nd Street north of Camelback. An example of a forced turn island that allows only right-hand turns can be seen on Lynwood Street at 7th, just south of McDonalds. And the Cancer Survivor's Park just north of the Burton Barr Library is an example of the artistic use of chicanes and center islands. Diverters can only be installed if traffic studies show high traffic counts and have the support of residents in the immediate area. And they're not cheap. Depending on exactly what the diverter is, installation can cost between $50,000 and $200,000 dollars to install. But the good news is that City funding is available to match the cost of diverters 9 to 1.
For more detail on various options, visit http://www.trafficcalming.org/.

Make a difference

We have a unique opportunity right now to turn our concerns about traffic into an asset. If you live in the Fight Back West area (7th to 16th Streets, Thomas to McDowell), please join us in designing long-term traffic solutions to enhance our neighborhood. Fight Back West meets the third Thursday of every month from 6:30-7:30pm in the Emerson School cafeteria at 10th Street and Palm. (Fight Back East will start to address the issues identified by Coronado residents who live between 16th and SR-51, and McDowell and the I-10, this fall.)

In the meanwhile, there are several things that each and every one of us can do right now that will make a difference at little or no cost:

ü Obey the speed limits.

Many traffic studies claim that it's the residents themselves who are the speeding culprits. Be aware of speed limits. If you obey them, the driver behind you is likely to do the same.

ü Wide streets invite cut-through and speeding. Parking cars along the street helps to visually narrow the speedways.

ü Plant trees in the easement strips. Again, trees visually narrow the speedway and naturally slow traffic speeds. They also provide shade to pedestrians, and add to the value of your property. The Fight Back Beautification Committee can help with info: andrea.delgaldo@highstream.net.

ü Report problem drivers.

If you are on the street with a speeding or reckless driver and no police are in sight, get the license plate number. You can email the plate number along with details of what/when/where to terry.sills@phoenix.gov and Officer Sills will send a friendly warning letter to the offender.