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FAQs

Q: What is the purpose of this website? This website’s primary objective is to provide information to individuals who live on a street that is maintained by the County of Los Angeles (not residents who live in one of the 88 cities of Los Angeles County). Although this website is available to anyone to view our focus is to provide County residents with information on when their street will be treated and how that treatment will impact their travel patterns. To see if you live on a County street click here.

Q: Yes, I live on a County street what’s the best way to use this website? Congratulations! You are one of the one million residents who live in the unincorporated County area of Los Angeles County. We certainly hope this website will help you get a better understanding of how we at the Department of Public Works strive to maintain our streets and keep them in the best possible shape. This website is designed to provide you with information to your questions about how we maintain County streets. Please continue to look at the questions below to learn more.

Q: How does the County determine the condition of my street? The County performs a visual survey on each street to collect information regarding the size and frequency of the cracks that are observed. Sometimes the cracks form readily identifiable patterns on the street surface which provide additional information on the condition of that street. The data is then inputted into the County’s Pavement Management System (PMS) which interprets the data and generates a rating from 0 (completely failed road) to 100 (road in excellent condition). We call this rating the Pavement Condition Index (PCI). A PCI is determined for every street in the County.

Q: How does the PMS convert the visual survey information into a PCI? Basically, the data that is fed into the software includes the size and frequency of the cracks as well as any crack patterns that are identified. From that information the PMS “grades” the street. Deductions from the starting score of 100 are made based upon the amount of cracks observed on the street. As the severity and frequency of the cracks increases on the street so does the deduction factor which reduces the overall PCI rating. In addition, each crack pattern also has a specific deduction factor which also contributes to reducing the overall PCI rating.

Q: How will the PCI rating affect treating my road? The PCI is very instrumental in determining what treatment is placed on the street. Typically, streets with PCI ratings above 74 are considered to be in good to excellent condition. Streets in this category are generally treated with a minor surface treatment that focuses on rejuvenating and sealing the road. Streets that have a PCI rating between 58 and 74 are in fair condition and are mostly treated with a thin paving layer. Streets that have PCI ratings below 58 are in poor or failed condition and require major pavement resurfacing or reconstruction.

Q: How does the Pavement Management System (PMS) work? The County’s PMS is a robust system that helps us manage our roads in many ways. First, it processes the pavement evaluations collected and determines the PCI for each street. Once the PCI is determined the PMS is very helpful in letting us know when to treat the streets. As was mentioned in the response to the question above as the PCI gets lower the treatments become increasingly more complex. As the PCI moves lower the treatment becomes costlier. The PMS is very helpful in allowing the County to identify streets before they reach a condition level that would require a more costly treatment. The PMS also has the capability to project future pavement condition data and perform benefit/cost ratios greatly assisting in developing a cost effective long term plan of treating County roads.

Q: What is Pavement Preservation? Many people understand the long-term benefits of performing preventative maintenance activities on their homes and automobiles. Painting your house every 10 years or changing the oil in your car every 3,000 miles are activities that preserve the value and improve the performance of these assets. It is commonly understood that these regularly scheduled preventative maintenance activities go a long way to keeping them in tip-top shape. The practice of applying preventative maintenance activities on pavements in good condition is an industry-wide practice called “pavement preservation.” Typically, the costs to preserving streets in good condition are significantly less (5 to 10 times) compared to the cost to rehabilitate or reconstruct streets.

Q: Does the County incorporate pavement preservation treatment strategies? When it comes to prioritization and management of road network systems, a lot of agencies tend to use the “worst roads first” approach or wait until road distresses become evident or reach a point where major rehabilitation or complete reconstruction is needed. The thought is “why use scarce resources to fix good roads while the bad roads are the ones that need repair the most? Until recently the County followed that same approach. Roads that were the most deteriorated were treated first, while pavements in good condition were left untreated. It became apparent that that this “worst roads first” approach would not stand up to the current financial, social, and environmental challenges that face our road network today. The ability to treat 5 to 10 times more area using the pavement preservation approach rather than treating the worst streets enables us to manage the condition of our road network better.

Q: What are the benefits of pavement preservation? As mentioned above one of the biggest benefits of moving forward with pavement preservation rather than resurfacing or reconstructing our streets is that more County streets can be treated because the cost of the treatments is significantly less than resurfacing and reconstruction treatments (5 to 10 times less). This cost difference stems from the fact that pavement preservation treatments are generally performed on the pavement surface, whereas rehabilitation and reconstruction involve the removal and replacement of one or more of the underlying pavement layers. Pavement preservation treatments have less of an impact on the environment.

Q: Does the County use environmentally friendly treatments? Yes, our Department utilizes 3 sustainable/green approaches in treating our roads. They include taking care of our roads that are in good condition first; Use recycled materials in treatment selections; and reutilize existing materials in-place. When compared to hot mix alternatives sustainable pavement treatments have reduced energy consumption and Greenhouse Gas Emissions (GHG) by approximately 80%. Also significant is the cost savings achieved. Since implementing the program in 2009 approximately $12.8 million has been saved using these sustainable approaches. See Green Measures for more information.

Q: Does the County use recycled materials in their pavements? Yes, our Department has implemented several approaches that are environmentally friendly. For the last fifteen years the County has utilized a pavement strategy that uses recycled tires in some of our paving projects. For each mile of road (two lanes) 4000 tires are recycled and diverted from landfills. During that time the County has recycled over 60,000 tires. In addition, our Department has recently started using Reclaimed Asphalt Pavement (RAP) in our pavement treatments further reducing our carbon footprint.

Q: Why are they performing a fog seal on our newly constructed road? To maximize the service life of your roads: every $1 spent maintaining a road in good condition in CA saves $6-$16 to rebuild a deteriorated one.

Q: When can I drive on a road that has had a fog seal treatment applied? Fog seals cure quickly. However, it is important to not drive on the freshly sealed surface for as long as construction signs indicate.

Q: Why are chip seals not used more often in residential areas? The texture of the aggregate rolled onto asphalt binder may be too abrasive. An abrasive surface is not desirable for neighborhood roads where children often play, fall, and hurt themselves. The chips in the chip seal may also de-bond from the asphalt due to turning motion caused by garbage trucks or vehicles maneuvering on and off drive ways.

Q: What are the environmental benefits of using a chip seal? The number one benefit of chip seals is that it preserves the underlying pavement, therefore extending the life of the existing pavement. In addition to preserving roads so they last longer, chip seals that utilize recycled tire rubber can divert waste tires from landfills.

Q: Why don’t we scrub seal all roads that display cracking? Scrub seals are most cost effective when utilized on roads that are structurally sound. We like to apply treatments on pavements that maximize the value of every dollar. It may not be cost effective to apply a scrub seal on a severely deteriorated pavement that is too far into its life cycle.

Q: Why do we not microsurface all our roads if it is so beneficial? Microsurfacing is more costly than a conventional slurry or chip seal. Treatments are selected based on both the cost and effectiveness of the treatment alternative based on the needs of the underlying pavements. We do not want to spend more than we need to in order to most cost effectively maintain your public roads.

Q: Why do we not see bonded wearing courses on all our roads? They are generally more expensive and difficult to construct than traditional dense graded HMA overlays. Geometric constraints may also prohibit bonded wearing courses to be utilized in urban environments due to the extra thickness associated with the permeable top wearing layer.

Q: What is Cold In-place Recycling (CIR)? CIR is a process where pavement is recycled in-place. Using a series of connected equipment the pavement is first removed by milling, sized, mixed with emulsion and then placed on the roadway. Paving equipment follows to provide the finished surface.

Q: Besides recycling the existing material, what is another benefit does CIR provide? CIR is a good alternative to traditional reconstruction. It performs well and municipalities have reported that CIR projects are 40% less costly than conventional pavement treatments.

Q: What is Cold Central Plant Recycling (CCPR)? CCPR is similar to CIR in that the pavement is recycled but is processed at a nearby location rather than in-place. The first step is similar to CIR in that the pavement is removed by milling but rather than sized and mixed with emulsion on site the pavement millings are hauled to a nearby location for sizing and adding emulsion. Once the millings are mixed with the emulsion the material is hauled back to the project site for paving.

Q: Why would you select CCPR instead of CIR? CCPR is generally performed on local streets. The CIR process requires a long train of equipment which makes using this process best for long arterial roads and not for residential roads.

Q: When would you perform FDR over CCPR or CIR? FDR grinds up the old pavement and uses it as a high quality base material. This recycled high quality base material provides a stronger foundation for projects that may be reconstructing in order to accommodate an increased traffic volume. The extent and severity of the distresses displayed by the old pavement is also a deciding factor.

Q: What is RAP? RAP is Reclaimed Asphalt Pavement. It is the material that results from grinding or milling the pavement surface.

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