Transportation
![](https://longmontcolorado.gov/wp-content/uploads/2024/08/Transportation.jpg)
Contact
303-651-8416
Hours of Operation
Monday – Friday, 8 am to 5 pm
Location
Transportation Department
350 Kimbark St.
Longmont, CO 80501
Roadway Improvements and Construction Updates
Shaping the Future of Transportation
There are many reasons why public organizations outsource work, but in most cases the reason is lower cost. Decisions to outsource can be driven by factors such as prohibitively high equipment costs, seasonal competition for labor, and needs for highly specialized skills.
Most municipal organizations are not equipped to perform large road construction projects. Furthermore, most major road maintenance work is performed in the summer months making it expensive to tie up a lot of money in staff and equipment for such a short time period. Many years ago, City staff painted all of the markings on City roads; however, that practice was discontinued when the high cost of owning and maintaining striping equipment made it much cheaper to contract the service. The same is true for most paving and concrete projects.
Contractors can often provide services at relatively low pricing because they are able to spread the cost of their labor and equipment across multiple municipal customers. Decisions to outsource some of the street work in Longmont are made by managers in the City’s Public Works and Natural Resources department with input coming from employees at all levels.
There are several good places to find information:
- City of Longmont interactive Cone Zones & Closures map
- City of Longmont Road and Bridge Construction webpage that highlights City projects under construction as well as those in design
- Boulder County Transportation
- Colorado Department of Transportation
During a snow/ice event, we will post updates on road conditions, Monday – Friday, on the City’s Winter Weather Road Report webpage. You can also view road conditions at points around town through our real-time Street Snow Cams.
Information about facility closures and other weather-related news will be posted to the City’s general News & Alerts page.
Longmont’s designated snow routes are designed to create an efficient network for accessibility throughout town using arterial and collector roadways. Arterial roads provide access to destinations across town (east-west or north-south) or to transportation networks outside of town. Collector roads move traffic in/out of neighborhoods and provide access to schools, hospitals, and other local destinations. Collectors also funnel traffic to arterial roadways.
Designated snow routes also must meet certain operational criteria for safety and drivability:
- Avoid left turns and U-turns
- Have available areas to pile snow as needed
- Have no surrounding obstacles or safety hazards
If you have to travel during or after a storm, plan your trip using snow routes as much as possible for the best conditions.
Learn more about the City’s snow & ice control program at LongmontColorado.gov/snow.
The decision to begin snow operations is based on many factors. These factors include predicted weather conditions, air and ground temperatures, and the potential for consecutive storms occurring in a short time period. Planning for a six inch snow storm will vary significantly depending on the month, forecasts, and existing road conditions.
We utilize a variety of advanced monitoring systems to gather timely and accurate information for planning and deployment, including:
- hourly & daily temperatures
- local and long term forecasts
- live street cameras
- pavement and air temperatures
- snow fall measurements
- radar maps
Learn more about the City’s snow & ice control program at LongmontColorado.gov/snow.
The safest place to be is behind the snow plow. Try to stay at least 100 feet behind a snow plow. The snow plow operator has limited visibility due to the weather conditions, size of snow plow and the blowing snow. Find more information and tips on our snow & ice control webpages at LongmontColorado.gov/snow.
We ask that drivers have patience when approaching a snow plow and refrain from passing it.
- Maintain a safe distance between your car and the plow.
- Signal your turning intentions, both in front of and behind plows.
- Refrain from passing any snow plow until the plow vehicle stops or turns.
- Avoid driving into a snow spray cloud that is created by the plow as this may cause a total “white out” of zero visibility to the driver.
- Use extra caution when driving near specialized wing plows, which have a regular 12 foot plow in the front and a 9 foot wing plow that hangs to the right. This wing plowing system clears both the driving lane and shoulder lane or two lanes of traffic in one pass, and it can be extremely dangerous for motorists who try to pass the plow.
Find additional snow guidelines and tips on our Snow & Ice Control webpages at LongmontColorado.gov/snow.
The City of Longmont uses two deicing products on roads referred to as Meltdown® Apex and Ice Slicer®. Both products are naturally occurring and approved for transportation system deicing by the United States Environmental Protection Agency (USEPA). Safety data sheets for these chemicals are linked below. A third product, sodium chloride, is used for anti-icing operations in a brine solution. Sodium chloride is common table salt. Deicing refers to the application of salts to driving or walking surfaces to melt existing snow and ice. Anti-icing refers to the application of salt to driving and walking surfaces before a storm to prevent snow and ice from bonding to the pavement and making it easier to clear. All deicing and anti-icing products are used in conformance with industry standards and guidelines to enhance effectiveness and minimize environmental impacts. Safety Data Sheets – Meltdown – Ice Slicer
Many people use sidewalks daily in order to travel through the city (even when it snows). Longmont Municipal Code states that you have 24 hours after snow or ice stops falling to clear your sidewalks. View the Municipal code.
Low to Moderate Snowfall
When snow fall is predicted to be low or moderate, consider waiting until the storm has ended and snow plow operations have finished before clearing your sidewalks. If you have sidewalks along a plowed street, shovel sidewalk snow onto your property instead of into the street; this will help minimize any additional snow that may inadvertently get pushed onto the sidewalk by plows. It’s impossible to completely avoid conflicts between snow removal on sidewalks and streets, so we have to work together and timing is key.
Heavy Snowfall
When significant snow accumulates, there are a few ways to handle the increased challenge of clearing sidewalks:
- Shovel multiple times during the storm to minimize build up
- Organize a neighborhood shoveling team
- Invest in a snow blowing machine
- Hire a contractor
The City of Longmont maintains traffic signals, performs road maintenance and provides snow and ice control along these state and U.S. highways that run through the city limits:
- State Highway 119 from Fordham Street on the southwest edge of Longmont to Fairview Street on the city’s eastern edge
- U.S. Highway 287 from Pike Road on the city’s southern edge to Park Ridge Avenue on the northern edge of Longmont
The Colorado Department of Transportation (CDOT) is responsible for state and U.S. highways outside of those parameters, including State Highway 66.
To submit feedback or a customer comment, please visit the CDOT Questions/Comments/Concerns webpage at www.codot.gov/topcontent/contact-cdot. Longmont is a part of CDOT Region 4 (North/Northwestern Colorado).
There are a few reasons why City of Longmont snow plow operators do not plow the parking lanes during a snow and ice event. Much has to do with the freeze/thaw cycle and what would be left behind for homeowners and drivers to deal with.
Snowed piled in the curb and gutter does not dissipate as quickly and can turn to ice when going through the freeze/thaw cycle. This ice blockage prevents the snow melt from reaching storm drainage inlets, leading to standing water that can freeze and extending how long it takes for the storm’s snow and ice to go away.
In the case of a large snow event, pushing the snow all the way to the curb leaves less room for cars to park within the parking lane.
The windrow (the technical term for that tiny mountain of snow left after plowing) remains smaller when only plowed to the edge of a bike lane or parking lane than it would be if taken all the way to the curb. Smaller windrows melt faster, returning our streets to to clear sooner. Additionally, larger windrows can result in a pile directly in front of a business entrance or homeowner’s driveway, making it more difficult for vehicles to leave and enter.
Roads are slightly crowned in the middle to facilitate drainage to the road edge where storm drains carry snow melt and rain water away from the road surface. If snow were plowed to the center of the road, Mother Nature’s freeze and thaw cycles would cause ice to continually build on the travel lanes, resulting in even worse traction. Our roadways, drainage systems and snow plow equipment are all designed to work best when snow is moved to the side.
Learn more about the City’s snow & ice control program at LongmontColorado.gov/snow.
CDOT has a much more uniform task of plowing long straight stretches of roads working in tandem. Their blades are much heavier and create greater downward force that would damage urban infrastructure such as storm sewers and other utilities in the roadway. Cities on the other hand must work in narrow roads around much more cross traffic and other obstacles such as storm drainage infrastructure. City equipment uses casters or hydraulics on blades to prevent them from damaging urban roads and infrastructure. In general, plowing in urban areas is more challenging and costs considerably more per lane mile. Learn more on our snow & ice control webpages at LongmontColorado.gov/snow.
Anti-icing is the process of spraying material onto the road before a storm that lowers the temperature at which ice will form on it. It is typically sprayed far enough ahead of a storm so that it will dry and reactivate when snow falls. The material only works under certain conditions, so you will not see crews conduct anti-icing in extremely cold temperatures.
To learn more about the City’s snow and ice operations, visit LongmontColorado.gov/snow.
Colorado’s climate undergoes significant temperature swings in the winter months due to abundant sunshine. Snow melts quickly during the day and freezes at night. Most of the freezing occurs in or near the gutter in the street. Extended freeze-thaw cycles after a major storm can cause significant ice build-up.
Find general information on our Snow & Ice Control webpages.
The City maintains 340 miles of centerline roadway in Longmont. About half of this – 140 miles – is plowed as part of the annual Snow & Ice Control Program. Snow & Ice Control is funded through the City’s Street Fund Sales and Use Tax, 3/4 of a cent on every dollar purchase in Longmont. This voter approved tax must cover a wide range of transportation projects and maintenance needs. Approximately $750,000 to $1,000,000 is spent each year on snow and ice operations.
Core Objectives
- Provide access to emergency services.
- Maintain the safest possible flow of commuter traffic through the city during the storm, emphasizing access to bus routes and schools.
- Restore normal driving conditions as soon as possible after the storm has ended.
Why Not Plow Everything?
- It would be very expensive (at least double the cost)
- Many residents would end up with an even greater snow removal burden on sidewalks and driveways, etc.
- Plowing would often create rows of snow in residential areas blocking driveways, street-parked cars and trash carts – resulting in worse conditions than leaving the road unplowed.
Residential Plowing: Only in Severe Cases
The Residential Snow Plow Program is launched only in severe storms to keep residential streets, or side streets, passable. We consider deploying this program to be an emergency measure only used under specific criteria because it employs such expensive and extensive resources. Because of these reasons, the residential plows do not deploy every time snow falls. Learn more on the Residential Plowing Program webpage.
Find a complete overview of snow & ice operations on the Snow & Ice Control webpages.
Snow plowing is intended to reduce the depth of snow accumulation on roads and improve traction. It is not intended to immediately expose the paved surface, nor does it maintain normal levels of surface traction. Accumulated ice and snow may remain on roads for days and even weeks when weather conditions inhibit thawing. Normal road speeds and stopping distances can be impaired for considerable lengths of time in snow climates.
Be Snow Savvy
Make certain that your vehicle is ready for winter driving conditions long before a storm rolls into town. Being prepared means that your vehicle has decent tires (snow tires or chains are smart investments, especially if your vehicle is without all-wheel drive or 4×4), good wiper blades, a working defroster and an ice scraper.
Learn more on our snow & ice control webpages at LongmontColorado.gov/snow.
We ask for cooperation from our residents in keeping their sidewalks clear from snow and ice. Many people use sidewalks daily to travel through the city (even when it snows). Longmont Municipal Code states that you have 24 hours after snow or ice stops falling to clear your sidewalks. View the complete code at bit.ly/longmont-snow-code.
City resources primarily focus on removing snow from the streets for safe emergency response and vehicle travel. City Parks Maintenance Operations does remove snow from some designated community sidewalks and trails; view a map of those areas.
If you need to travel during or after a storm and are unable to walk along a sidewalk in certain areas, please use the maps on the Snow Routes webpage to plan your trip, or walk through a residential area where sidewalk clearing is required. (This may mean going down or over a block.)
Find more information on our Snow and Ice Control webpages.
Generally, arterial and collector streets are swept monthly during spring, summer, and fall or April through October, as is the Downtown area. Business and industrial areas are swept six times per year and residential areas are swept at least three times per year.
Learn more about Street Sweeping on our program webpage.
Contract sweeping services are used for peak seasonal sweeping operations during fall leaf season and periodically for spring clean-up. Utilization of contractors during the fall is necessary in order to clean up the leaves prior to freezing temperatures. The contract sweepers mainly focus on the more established areas of the City with mature trees; the city sweepers take care of the remaining streets.
Learn more about Street Sweeping on our program webpage.
Keeping the roadway in front of your house free of large objects and obstructions is the best way to assist street sweeping crews’ clean-up efforts. Find a list of additional tips to help out the sweepers on our Street Sweeping webpage.
If your request is non-emergency, contact Transportation to request an inspection. If sweeping is deemed appropriate, it will typically be scheduled for completion during a Friday. If you see debris in the street creating an immediate hazard during normal business hours (Monday – Friday, 8 am – 5pm), contact us. After hours, call Police Dispatch.
During Fall and Spring
During the citywide leaf sweeping program each fall and spring, we cannot take special street sweeping requests. The leaf sweeping program operates on a tight schedule and, in order to sweep the entire city, we cannot accommodate special requests or call-backs. Multiple trips will be made to ensure a clean sweep; please be patient and wait for the next trip through your neighborhood.
Learn more about where and when we sweep on our Street Sweeping webpage.
Sweeping is divided into routes based upon the frequency. Arterial and collector streets as well as Longmont’s downtown receive the most traffic, thus debris accumulation is greater in these areas, so they are swept more frequently.
The street sweeping routes and scheduling have been designed to not interfere with trash collection and to ensure that bike paths and bike lanes are captured. Additionally, it is our standard practice to sweep snow routes after snow events.
Learn more on our Street Sweeping webpage.
Sweeping routes and trash routes are scheduled to avoid street sweeping when trash carts are at the curb for pick-up. On rare occasions, sweepers may be working in a neighborhood that is scheduled for trash pick-up. We do our best to minimize these instances.
Learn more about Street Sweeping on our program webpage.
There are many reasons why public organizations outsource work, but in most cases the reason is lower cost. Decisions to outsource can be driven by factors such as prohibitively high equipment costs, seasonal competition for labor, and needs for highly specialized skills.
Most municipal organizations are not equipped to perform large road construction projects. Furthermore, most major road maintenance work is performed in the summer months making it expensive to tie up a lot of money in staff and equipment for such a short time period. Many years ago, City staff painted all of the markings on City roads; however, that practice was discontinued when the high cost of owning and maintaining striping equipment made it much cheaper to contract the service. The same is true for most paving and concrete projects.
Contractors can often provide services at relatively low pricing because they are able to spread the cost of their labor and equipment across multiple municipal customers. Decisions to outsource some of the street work in Longmont are made by managers in the City’s Public Works and Natural Resources department with input coming from employees at all levels.
Arterial and collector streets receive more traffic, debris accumulation is greater, and they are therefore swept more frequently.
Learn more about Street Sweeping on our program webpage.
Residential street sweeping will be conducted between the hours of 7 a.m. and 7 p.m. A street sweeping “night shift” will sweep industrial areas and within the boundaries of downtown Longmont.
Learn more about Street Sweeping on our program webpage.
Longmont’s sweeping program is conducted primarily for storm water and air quality compliance, though safety and aesthetic benefits are also realized through sweeping.
Learn more on our Street Sweeping webpage.
In order to make the most efficient use of available resources and equipment, timed or daily scheduling of residential routes is currently not practicable. Please review our sweeping frequency table found on the Street Sweeping webpage for more information on how we schedule and prioritize sweeping.
The City of Longmont maintains traffic signals, performs road maintenance and provides snow and ice control along these state and U.S. highways that run through the city limits:
- State Highway 119 from Fordham Street on the southwest edge of Longmont to Fairview Street on the city’s eastern edge
- U.S. Highway 287 from Pike Road on the city’s southern edge to Park Ridge Avenue on the northern edge of Longmont
The Colorado Department of Transportation (CDOT) is responsible for state and U.S. highways outside of those parameters, including State Highway 66.
To submit feedback or a customer comment, please visit the CDOT Questions/Comments/Concerns webpage at www.codot.gov/topcontent/contact-cdot. Longmont is a part of CDOT Region 4 (North/Northwestern Colorado).
During citywide sweeps each fall and spring, it’s common that dump trucks will accompany sweepers due to the large amount of debris being collected. In order to be most efficient while sweeping, the street sweepers will dump into the trucks, so they do not need to drive to the city’s Waste Diversion Center multiple times a day.
Learn more about this program on our Street Sweeping webpage.
There are many reasons why the sweeper may not have been able to remove debris from your street. Most often, it’s because items such as cars, bicycles, toys, basketball hoops and refuse containers are blocking the roadway. Vehicles parked too close to each other for the sweeper to maneuver between them are another cause. Low hanging trees and shrubs can prevent sweepers from cleaning in front of your home as well. Although it is a goal to also have the streets looking clean, the expense of notification – signage, mailings, and/or barricading – is cost prohibitive.
During Fall or Spring
During citywide sweeps occurring each fall and spring, the street sweepers fill up faster and need to dump more often. If a sweeper pulls off your street without finishing during this time:
- The sweeper may need to go dump or fill with water and then return.
- They may have been called off to clean up after an accident or glass in the roadway.
- Time may have run out and the sweeper will return another day.
Learn more about our sweeping program on our Street Sweeping webpage.
To better serve the traveling public, the City of Longmont has street improvement programs included in its capital improvement plan. Improvements are scheduled on an annual basis according to need and available resources. Street improvements include resurfacing, widening and other major improvements which are not categorized under normal street maintenance programs. In addition, sidewalk repair and replacement is included in these efforts.
Information can be obtained on streets currently scheduled for improvements by visiting our Road and Bridge Construction webpage as well as our Paving and Concrete webpage, which identifies projects selected as part of the Pavement Management Program.
If you come across any areas during your travels through Longmont which need attention or repair, please let us know by contacting Transportation.
If a pothole is so large or deep that it is presenting a safety hazard for motorists or pedestrians and it is a weekend, please call and report it to Longmont Public Safety Dispatch.
The City provides repair service for concrete sidewalks, curbs, gutters and concrete pavements that are within City rights-of-way. For non-dangerous repair needs, please contact Transportation.
Damaged sidewalks and concrete that are dangerous to pedestrians and vehicles should be immediately reported by contacting Transportation between 8 am – 5 pm, Monday through Friday. After hours and on weekends, these types of emergencies should be reported to Longmont Public Safety Dispatch.
When conditions warrant, temporary repairs will be made, followed by permanent repairs as soon as possible. Routine service requests are assessed, rated, prioritized and scheduled for the appropriate repair.
Please contact Transportation; you can submit a request online or via telephone.
There are many reasons why public organizations outsource work, but in most cases the reason is lower cost. Decisions to outsource can be driven by factors such as prohibitively high equipment costs, seasonal competition for labor, and needs for highly specialized skills.
Most municipal organizations are not equipped to perform large road construction projects. Furthermore, most major road maintenance work is performed in the summer months making it expensive to tie up a lot of money in staff and equipment for such a short time period. Many years ago, City staff painted all of the markings on City roads; however, that practice was discontinued when the high cost of owning and maintaining striping equipment made it much cheaper to contract the service. The same is true for most paving and concrete projects.
Contractors can often provide services at relatively low pricing because they are able to spread the cost of their labor and equipment across multiple municipal customers. Decisions to outsource some of the street work in Longmont are made by managers in the City’s Public Works and Natural Resources department with input coming from employees at all levels.
You can see a list of projects on the Pavement Management Program webpage or by contacting Transportation. If your street has been selected for treatment, you will receive a project notification letter in the mail. Construction typically begins in the spring or summer. As construction approaches, a door hanger will be posted on your home to inform you more specifically of the upcoming activities.
During normal business hours (Monday – Friday, 8 am – 5pm), contact Transportation.
After hours, call Police Dispatch and Storm Drainage crews will be contacted.
Please contact Transportation between 8 am – 5 pm, Monday through Friday.
After hours emergencies, such as damaged stop signs and signs that have been hit creating a hazard within the roadway, should be reported to Longmont Public Safety Dispatch .
The City maintains trees and shrubs located on City right-of-ways which may be blocking visibility of signs and view of oncoming traffic. Please report issues or concerns in such areas to Forestry Services. If the trees or shrubs are on private property please contact Code Enforcement.
Alleys that are open to public passage are maintained by the City. Crews are assigned to patch potholes, grade and repair the alley surfaces. Alleys requiring maintenance should be reported by contacting Transportation. Problems related to trees in alleys can be reported to the Code Enforcement Department .
The City of Longmont maintains traffic signals, performs road maintenance and provides snow and ice control along these state and U.S. highways that run through the city limits:
- State Highway 119 from Fordham Street on the southwest edge of Longmont to Fairview Street on the city’s eastern edge
- U.S. Highway 287 from Pike Road on the city’s southern edge to Park Ridge Avenue on the northern edge of Longmont
The Colorado Department of Transportation (CDOT) is responsible for state and U.S. highways outside of those parameters, including State Highway 66.
To submit feedback or a customer comment, please visit the CDOT Questions/Comments/Concerns webpage at www.codot.gov/topcontent/contact-cdot. Longmont is a part of CDOT Region 4 (North/Northwestern Colorado).
Proper maintenance is what keeps your car or house in good condition over many years, and the same rule applies to streets. If an appropriate maintenance treatment is applied while a street is still in relatively good condition, the street will continue to function properly for many years. Without proper maintenance, streets will deteriorate over time to a point at which reconstruction is needed. Complete street reconstruction is extremely expensive and results in greater impacts to traffic.
The City of Longmont’s Pavement Management Program serves to monitor conditions and conduct strategic maintenance treatments. By doing this, we keep overall program costs down and prevent much larger, expensive road repairs.
There could be many reasons as to why there are “no parking” signs in your neighborhood. Street signs often have information on them, but if not please contact Transportation.
The City of Longmont frequently receives requests from parents and homeowners associations for “CHILDREN AT PLAY” signs in residential areas. These requests stem from concerns for the safety of their children in the street and near their homes. Unfortunately, these requests are based on a false belief that such signs provide protection, though, studies have actually found these signs to be deceiving and ineffective.
For this reason, the City of Longmont will not install, or allow to be installed, Children at Play signs. These signs have not been shown to increase driver awareness and are not recognized as a standard highway sign by the Federal Highway Administration. Studies have shown no evidence that these signs prevent pedestrian accidents or decrease the vehicle speeds. Children at play signs also give parents and children a false sense of security and can be misinterpreted to mean that it’s okay to play in the street. It is important that parents teach their children about the dangers of playing near or in the street and should discourage them from doing so.
Another consideration with these signs is that nearly every street has children on it and would be require a sign to be posted on every block. This is not only impractical but would render the signs meaningless. Streets with no signs might also imply that no children live there and could lead to unsafe driving on those particular streets. Warning signs are effective tools if used sparingly to warn motorists of uncommon hazards that are not apparent to drivers. The use of unnecessary signs generally promotes disrespect for all signs. To address pedestrian safety, specific warning signs for school zones, pedestrian crossings, playgrounds and other recreational areas are used where they are truly warranted.
The City of Longmont does provide “Please Slow Down” yard signs that can be obtained from the Traffic Operations Department. These are for residents to place in their yard as a reminder to drivers. Yard signs are free of charge and can be picked up at the Development Service Center at 385 Kimbark Street, Monday through Friday during normal business hours.
Find more information about Traffic Operations.
Please contact Transportation.
State law says that a crosswalk exists at any intersection whether or not markings exist. Pedestrians and motorists have the same legal rights and duties at unmarked crosswalks at intersections as they do at a location with crosswalk markings.
Marked crosswalks are not installed arbitrarily. The main function of a marked crosswalk is to serve as a guide to indicate to pedestrians the appropriate place to cross. They are also used to warn motorists of potential pedestrian crossings. However, they are only effective for this purpose where pedestrian volumes are relatively high and the potential for conflict with vehicles is also high. Unwarranted or random crosswalks that are seldom used by pedestrians may breed disrespect for the devices and make the ones that are truly necessary even less effective.
Several recent research studies have suggested that pedestrian accident rates are often higher in marked crosswalks than they are in unmarked crosswalks. So, we are very careful where we put them. In general, the City of Longmont installs marked crosswalks at signalized intersections, along designated walk to school routes where children must cross busy streets at uncontrolled locations and at other locations where the proper crossing location would not otherwise be obvious. In addition, the City will evaluate the need for crosswalks at other locations based on the volume of pedestrians and vehicles along with other factors such as the number of lanes and the speed of traffic.
View the City of Longmont’s Pedestrian Crossing Treatment guidelines.
Traffic signals are designed to assign the right-of-way at congested intersections that would otherwise have excessive delays and to address certain types of safety problems, particularly right angle accidents.
Unfortunately, traffic signals can also cause an increase in other types of accidents, especially rear-end accidents. At an intersection that is not prone to right angle accidents, installing a signal might actually increase the overall number of accidents. In addition, unwarranted signals can cause unnecessary stops and idling that lead to excess fuel consumption and increased air pollution. Traffic signals can also be very expensive to install, running between $75,000 – $200,000.
Instead of using arbitrary standards that could vary with each jurisdiction, the Federal Highway Administration has established a set of standards using the experience and expertise of traffic professionals nationwide. Both the State of Colorado and the City of Longmont have adopted the national standards for the placement of traffic signals.
So, the City only considers signalization at intersections that meet or are projected to meet (for a new road) the standards. These standards consider:
- vehicle volumes
- pedestrian volumes
- amount of delay
- number of accidents
A traffic signal can only be installed as determined by a traffic engineering study and when at least one traffic signal warrant condition has been met. Nine traffic signal warrant conditions are identified in the Manual on Uniform Traffic Control Devices, and an intersection must meet at least one warrant.
The nine warrant conditions are:
- Traffic Count Data: Eight Hour Vehicular Volume
- Traffic Count Data: Four-Hour Vehicular Volume
- Traffic Count Data: Peak Hour
- Pedestrian Volume
- School Crossing
- Coordinated Signal System
- Crash Experience
- Roadway Network: Intersections of Major Routes
- Intersection Near a Grade Crossing: Railroad
Intersections with conditions that meet the standards may benefit from the installation of a signal. Intersections that don’t meet the standards typically would see more negative impacts than benefits if a signal was installed.
Find more information about Traffic Operations.
- Synchronized Signals
Along arterial and busy collector streets with several traffic signals, the traffic signals are usually synchronized to help provide coordinated movement along the primary street. The emphasis of this strategy is to minimize vehicle stops & delay, the amount of fuel consumed, and air pollution produced.
A fixed cycle length must be used at each intersection along the corridor in order to keep the signals synchronized (a cycle is the time it takes to give a green light to all of the different movements at an intersection).
Signal cycle lengths of 50 to 115 seconds are used in Longmont and most of this time must be devoted to giving green lights to the higher volume arterial street approaches. Thus, drivers who pull up on a side street just after the green light ended for their intersection approach may have to wait more than a minute before the green light is once again available to the side street. This often feels like a long time when you are waiting, but it is actually necessary for overall traffic efficiency.
Synchronization works better on some roads than on others due to variables such as signal spacing, travel speeds, and the amount of interference from unsignalized access points
- Isolated Signals
Isolated intersections are those with no other nearby signals, and where vehicles arrive mostly in random fashion. At isolated intersections there is less opportunity to minimize stops as there is no way to predict when vehicles will arrive.
The approach we use at these locations is to time the signals in order to reduce stops and delay experienced by drivers. Depending on the intersection, this can either be achieved by using “semi-actuated” timing where the major streets gets more time and the side street only gets a green light when a car is present, or “fully actuated” timing where vehicle detectors are on all approaches and cycle only in response to the actual demand on each approach.
While delays are typically short at fully actuated intersections, the downside to this timing philosophy is that more drivers have to stop. That is the nature of the least delay timing solution. The amount of time spent waiting is minimal but most drivers end up stopping at least for a short time. That makes this strategy inappropriate along higher volume arterial streets.
Find more information about Traffic Operations.
At many intersections in Longmont with protected/permissive left turns, we have chosen to “Lag” the left turn arrow phase rather than “Lead” the left turn phase. This is often beneficial to overall capacity of the intersection, as most of the left turning traffic at these intersections can make a permissive left turn during the through phase. If the vehicles waiting to turn left are not able to do so during the through phase, they will be given a green arrow to clear the intersection. If all left turners are able to clear the intersection before the end of the through phase, there is no need to serve the left turn protected phase. This means that higher volume through approaches can continue to have the green light, and there is less overall “Lost Time” at the intersection. Lost time is time that is not used for any green movements – the yellow and all red phase. Yellow and red times are typically about 5-7 seconds. While this may not seem like much time, it adds up over the hours. For example, an intersection with a 100 second cycle length will serve each phase 36 times an hour (3600 seconds/100 seconds/cycle = 36). 36 X (6 seconds yellow + red) = 216 seconds, or 3 ½ minutes of green time that is not available for other movements in one hour. This impact is even more pronounced when there is more than one through lane on an approach – that is 3 1/2 minutes per hour less green time available for each through lane.
Find more information about Traffic Operations.
The City of Longmont maintains traffic signals, performs road maintenance and provides snow and ice control along these state and U.S. highways that run through the city limits:
- State Highway 119 from Fordham Street on the southwest edge of Longmont to Fairview Street on the city’s eastern edge
- U.S. Highway 287 from Pike Road on the city’s southern edge to Park Ridge Avenue on the northern edge of Longmont
The Colorado Department of Transportation (CDOT) is responsible for state and U.S. highways outside of those parameters, including State Highway 66.
To submit feedback or a customer comment, please visit the CDOT Questions/Comments/Concerns webpage at www.codot.gov/topcontent/contact-cdot. Longmont is a part of CDOT Region 4 (North/Northwestern Colorado).
Pedestrian signals are timed to allow a person to walk across the street before conflicting traffic gets a green light. The “WALK” portion is only intended to get pedestrians started across the street. It is typically only on long enough for a person to make sure it is clear and then start walking.
Throughout Longmont, the traditional Hand/pedestrian symbolic signal indications were replaced with the countdown pedestrian signals several years ago. The timer counts down to show how much time you have left to cross the street. It helps the pedestrian know how much more time they have to cross the street after the “walk” has been displayed.
Note: Just as vehicles must often be detected by our detectors to get a green light, pedestrians must use the push buttons to let the traffic signal know they are present and want to cross. If the button is not pushed, the pedestrian signal may not be activated and the green signal light may only stay green as long as vehicles are on the sensors. If there are only a few cars, the green light won’t last long enough for a pedestrian to get across the street. The buttons provide more time for pedestrians to get across the street.
At many signalized intersections in Longmont, you may see that the walk indication automatically comes up when the parallel through phase for traffic is running. We put these pedestrian signals on “recall” along major corridors where there is enough green time for pedestrians to cross the street.
Find more information about Traffic Operations.
The City installs left turn arrows in two instances:
- where they can reduce the overall delay experienced by motorists; or
- at locations that have an identified left turn accident problem that a left turn arrow can help improve.
While left turn arrows typically decrease the delay experienced by left-turning drivers, they also usually increase the delay and number of stops for non-turning traffic. This is because some green time must be taken from other movements in order to give green time to the arrow. It is not simply a matter of putting in an arrow to improve things for left turning traffic.
At locations where there is a high volume of left turners and left turn delays are high, the increase in delay to through traffic caused by an arrow can be offset by the decrease in the delay to the left turners. However, where the through traffic volume is considerably higher than the left turning traffic volume, the benefit to left turning traffic usually does not outweigh the increase in delay and stops for through traffic. If arrows are installed under these circumstances not only does it lead to more congestion, it also leads to an increase in fuel consumption, vehicle emissions and, potentially, an unnecessary increase in rear end accidents (because of the increase in stops for through traffic).
Most of the left turn arrows in Longmont operate in a protected/permissive mode. That is, cars are allowed to turn left when the arrow is on and then continue to turn left after yielding to oncoming traffic when the green ball or flashing yellow arrow is displayed. Left turn arrows that operate in a protected/permissive mode are an efficiency tool much more so than they are a safety tool. Where left turn volumes are high and delays to left turners are correspondingly high, arrows can be used to decrease the overall delay at an intersection. Under those conditions, arrows are installed.
Find more information about Traffic Operations.
A four-way stop can be very useful at intersections where the traffic on each approach is approximately equal and steady throughout the day, or at an intersection where certain types of accidents have consistently been a problem. However, when this type of control is used when these conditions do not exist, it may actually cause more problems than it solves. Interestingly, most research has found that stop signs do not decrease the overall speed of traffic. Thus, we do not use them for speed control.
An inappropriately placed stop sign is often ignored by motorists either because of contempt for the sign or because the driver simply did not expect it to be there. This can lead to an increase in accident potential at the intersection for crossing motorists and pedestrians who falsely believe an oncoming vehicle will stop because of the sign. This problem also tends to increase the potential for rear end accidents where one car stops for the sign but the following car does not. In addition, increased vehicle delay, increased fuel consumption, more noise pollution and more air pollution result when an inappropriately placed four-way stop is present.
To help ensure that four-way stops are only installed when necessary and thus avoid the problems associated with them, engineering standards have been established to determine the need for four-way stops. These “warrants” have been established by the U.S. Department of Transportation based on the expertise and experience of transportation engineers nationwide. These warrants are published as part of the Manual on Uniform Traffic Control Devices (MUTCD) by the Federal Highway Administration. The State of Colorado and the City of Longmont have adopted the MUTCD as the guide for installation of all traffic control devices including four-way stops.
Find more information about Traffic Operations.