Street Maintenance and Project Descriptions

Did you recently swerve to avoid a pothole? Is your street being dug up for water line repairs? We are the Division that is responsible for the repair of these situations! We do repair work on streets, guardrails, and bridges in the City of Austin.

This work includes maintenance of all road and bridge structures within the City's public right-of-way; including patching potholes, resurfacing streets, utility cut repairs, guardrail, and storm response. The Division also conducts smaller sidewalk and ramp projects funded under the Capital Improvement Program.

Crack Sealing A preventative maintenance measure which consists of sealing the cracks in the pavement with a sealant or asphalt sealing product to prevent the moisture from penetrating into the base and subgrade material.

Sealcoat A thin asphalt emulsion surface treatment covered with aggregate, used to waterproof (seal) the existing street surface and to increase skid resistance. Sealcoat typically includes some crack sealing and level-up (see definition below) work and may include a moderate amount of other preparation work including limited curb and gutter replacements, surface replacements, and full-depth repairs.

Level-up Minor depressions and surface roughness in limited areas may be addressed by placing a small amount of asphaltic level-up material before resurfacing with a sealcoat or overlay.

Surface Replacement If there are no noticeable base or subgrade failures, but the existing HMAC surface is exhibiting extensive cracking, roughness, or surface rutting; the asphaltic pavement surface needs to be replaced which is typically the top 2” or 3” inches.

Full-Depth Repair If base or subgrade failure has occurred because of severe cracks or settlements of a pavement section, that pavement section needs to be replaced or repaired full-depth (typically 10” to 14”) to a condition equal to or better than the surrounding pavement sections. If the repair area due to failure is very localized (e.g. less than 8ft x 16ft), it is called a Spot Repair.

Slurry Seal Slurry seal is a mixture of an asphaltic oil and water (emulsion) and crushed rock aggregate that is spread over the street at about ¼" thickness. The slurry "cures" when the water evaporates leaving only the asphalt to coat the crushed rock. The asphalt acts as a binder to hold the slurry together and bond to the existing pavement. The Slurry Seal protects the existing street surface from the effects of aging and oxidizing and increases the skid resistance. Slurry Seals typically include some crack sealing on cracks 3/16” and larger. Prep work may also include a minor amount of level-up and surface replacement areas depending upon conditions; however, slurry seal is typically used on streets that are in good to excellent condition. In general, a Slurry Seal does not extend the life cycle of the pavement, it helps preserve the remaining utility and original design life of the pavement. Slurry seal is strictly a preventative maintenance operation.

Microsurfacing Microsurfacing may be used on heavier classes of streets like arterials instead of a slurry seal for the added durability. Microsurfacing may be also used when the existing pavement is rougher than a typical Sealcoat or Slurry Seal candidate street, but does not warrant an overlay. Microsurfacing is very similar to a thick slurry seal and is placed with the same equipment. It can achieve some large area leveling and smoothing effects like filling in ruts and depressions as well as have most of the full surface protection benefits of a Sealcoat. It should be noted that although Microsurfacing has some additional benefits over a Sealcoat, it cannot seal large amounts of surface cracking as well as a sealcoat.

PM Overlay A PM overlay consists of a single layer of hot mix asphaltic concrete (minimum of 1½ inch thick; but typically 2”) used to level, waterproof, and restore the original street shape and ride. Although it is not intended to add a substantial amount of structural value to the pavement section, it is a minor structural improvement, nonetheless.

Structural Overlay A Structural Overlay is placing one or more layers of asphalt mix (min 2 inches total thickness) over an existing pavement. Overlay increases the structural value of the pavement section and therefore the life cycle of the street. Overlay can be categorized as a Preventative Maintenance (PM) Overlay, mentioned in the previous section, or a Structural Overlay. Structural Overlay typically includes similar preparation work to PM Overlay projects though typically including more extensive amounts of curb and gutter replacements, surface replacements, and full-depth repairs.

Minor Rehabilitation Minor rehabilitation typically includes less than 30% FDRs (see definition), limited SUR (see definition) areas for severely deteriorated existing HMAC pavement, thickened edge milling, limited curb and gutter repairs, and a structural overlay.

Major Rehabilitation Major rehabilitation typically includes greater than 30% but less than 60% FDRs, more SUR areas for severely deteriorated existing HMAC pavement, thickened edge milling, extensive curb and gutter repairs as necessary, and a structural overlay.

Localized Street Area Reconstruction When the pavement of a street deteriorates to a point where more than 60% of the pavement requires full-depth repair (generalized failure), it should be totally reconstructed. Street area reconstruction consists of replacing the complete pavement section including the curb and gutter as necessary. It may involve minor drainage improvements; adjustments to the street profile, cross section, and width; and very minor adjustments can be made to the alignment.

Complete Street Reconstruction This category is for replacing all of the infrastructure components maintained by Public Works in the right-of-way and consists of replacing the complete pavement section, all of the curb and gutter, driveway aprons, drainage system improvements, sidewalks and ramps. This is a traditional CIP street and drainage improvement project. Complete street reconstruction can incorporate moderate changes to the street alignment, profile, cross section, and roadway width.

New Street Construction This category is for constructing new infrastructure components maintained by Public Works in the right-of-way and typically consists of a standard street section in accordance with transportation plans or current traffic levels at a minimum, curb and gutter, driveway aprons, a new drainage system, sidewalks and ramps, traffic signals, signs, and markings. This is a traditional CIP street network capacity expansion project. Complete street construction can incorporate major changes to the existing natural grade for proper street alignment, profile, cross section, and roadway width. New alignments typically require the purchase of right-of-way and may require bridge structures which can have a huge impact on the project cost. Effective project costs with ROW, bridges, business relocations, and condemnation settlements can easily range to well over $1M/LM.

Need to report a pothole? Vegetation covering a stop sign? Sign down? Call 3-1-1 with the location!