Chip Seal 2011 Pilot Project
Neighborhood: South Mercer Island
Project Type: Streets
Project Timeline (Estimate): Late August through early September 2011
Description: A new chip seal pilot program will resurface selected residential streets starting August 22nd through early September. Preserving and improving the Island’s residential streets is a priority for the City. Given the current economy, we are looking at ways to stretch our limited capital improvement dollars.
A chip seal (technically called a Bituminous Surface Treatment) can add between 7 to 15 years to the life of an asphalt pavement, and can do it for a fraction of the cost of the typical method, hot mix asphalt (HMA) overlay. Roads for this year’s pilot project were selected based on several factors, including their physical condition, age, and number of years until they would receive a HMA overlay. The maps on the below show the streets that are included in this project.
This project will include the following activities:
- Chip Sealing: Applying liquid asphalt to the roadway, followed by a layer of fine rock chips (typically 3/8” in size). The rock is embedded into the liquid asphalt with rollers and allowed to set up overnight. The excess rock chips are swept up and removed the next day. On some streets, this chip seal process will be performed twice, to create a double chip seal with added strength. Sweeping will follow to collect as much loose rock as possible after chip placement and again just before the Fog Sealing.
- Fog Sealing: A few days after the second chip seal is placed, the surface is sprayed with a layer of diluted asphalt emulsion. This final asphalt application improves the rock chip adhesion to the road and gives the surface a uniform black appearance. This process will require the roadway to be closed (one side at a time) for several hours so that the fog seal can dry. A final sweep over the following weeks will collect the last of the loose rocks.
For the chip seal process to be a success, the understanding and support of residents is greatly appreciated. The chip seal process will only take 2 to 3 days to perform, but the process may be spread over a couple of weeks. While work is underway, all roadways will need to be clear of vehicles. “No parking” signs will be posted in advance. Generally, access to streets and driveways will have only minimal delays; however, some short duration closures may be necessary. The contractor will attempt to keep half the street open as work proceeds. Please avoid driving on or walking on freshly applied asphalt, as it will track onto your driveway and into your house. Please watch for flaggers and follow their directions – if they stop you or make you drive around the block, it may be to keep you off the fresh, wet asphalt. Also, expect a couple weeks of loose rocks on the roadways, as it will take several times of sweeping to pick all of them up.
Contact Information: Clint Morris, Maintenance, 275-7807, email@example.com