What is cape seal?
Cape seal uses the advantages of two sealing and rehabilitation methods combined. It is the application of a chip seal followed within a few weeks by a slurry seal.
Why a cape seal?
A cape seal is applied when the pavement deterioration is greater than what a slurry seal is designed to correct, yet has not deteriorated to the point of requiring an expensive asphalt overlay. A cape seal prevents water penetration reducing subsequent damage to the road bed, along with providing a new wearing surface. Cape seals are used on residential streets due to its ability to provide the strength of a chip seal with the smoothness of a slurry seal. Used with crack sealing and surface patching, a cape seal significantly extends the life of a neighborhood street.
How is cape seal applied?
First a chip seal is applied using standard application methods
Second after the chip seal cures (usually after one to two months), the slurry seal is applied leaving a smooth surface.
How are streets identified for cape seal?
Using our Pavement Management System, selected streets are identified by their condition. Typically, these are streets that a slurry seal alone would no longer be effective. Each street is then researched for other pending utility projects (water, sewer lines, etc.). Finally, each potential street is field-verified for condition and community value and added to the annual contract as budgeted funds allow.
What will City crews be doing to prepare the streets for a cape seal?
City Streets Section crews will be sealing cracks and patching most defects prior to the actual cape seal application. These activities may require more than one visit to your street due to the specialized nature of each repair method.
How is the project funded?
Funding for the cape seal project is provided through revenues collected from gas taxes and utility franchise fees.
How will this affect access to our street?
During the chip seal phase, only local traffic access will be allowed on some streets, while other streets will have traffic controlled by flaggers and a pilot car. In both situations, you can expect short duration interruptions to traffic flow. You will be able to drive on the chip seal fairly soon, though we advise reduced speeds for a few days to minimize flying rock. During the slurry seal phase (six to eight weeks) the street will be closed to all traffic for approximately four to six hours. To minimize disruption to businesses, some areas will be treated with slurry on a weekend. We will notify you at least 72 hours in advance prior to commencing work on your street.
What about the loose gravel on the streets?
A certain amount of aggregate applied in the chip seal process will work loose as the chip seal cures. We will post advisory signs and ask that vehicle speeds be kept down (15 to 20 mph) to prevent flying rock from damaging other vehicles until the loose rock has been removed. The contractor will be sweeping up loose rock in the days immediately after the chip seal has been applied. The contractor will again sweep the chip seal areas immediately prior to the application of the slurry seal. In the interim, City forces will sweep as needed.
What else can we expect?
Chip seals leave behind a coarse, abrasive surface that can cause increased tire noise and a rough ride for bicycles, skateboards, roller blades, etc. There can also be dust present from traffic for a few days after the application. The slurry seal phase will significantly reduce tire noise, eliminate any dust, and bind the remaining rock into a smooth and hard wearing surface.