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placed on the streets over a layer of aggregate base which now makes up the existing street section. The Kohlman Lane Area Streets have continued to deteriorate over the years with the streets having a weighted average PCI rating of 21 (scale from 1 to 100). The streets in the rating, having a length of 0.65 miles, consist of Beam Avenue, Kohlman Court, Kohlman Lane, Linden Lane, and Meadowlark Lane. The Keller Parkway street section between Arcade Street and Kohlman Lane is a County Road and does not warrant replacement, but due to proposed sanitary sewer and water utility extensions in this area, the cost estimate assumes a full width reconstruction. It is necessary to reconstruct the neighborhood streets to improve serviceability and drainage (including treatment), extend water and sanitary sewer utilities, meet city standards, and relieve the maintenance department of constant repairs such as patching. Longitudinal and lateral cracks are apparent on a majority of the streets. Inadequate crown allows water to pond and traverse the street section, further deteriorating the roadway. The freeze and thaw cycles that happen every spring, combined with the old age and poor design of the streets, are responsible for the declining roadway conditions. Also, the poor soils beneath the road section appear to have never been excavated and replaced with suitable subgrade materials. The poor subgrade soils under the neighborhood streets translate to an inadequate support for the existing roadway section. To determine the existing pavement thickness and subgrade soil type, fourteen soil borings were taken within the project area by Braun Intertec Corporation. Five of the fourteen soil borings had traces of ground water at depths ranging from ten to fifteen feet below the road surface. The geotechnical evaluation report provided insight into present condition of the native subgrade materials and recommendations for a proper design which is discussed later in this report. The streets within the proposed project area have deteriorated to the point where reactionary maintenance is no longer effective. Crack sealing, seal coating and overlaying are no longer cost effective solutions to maintain these streets. To be cost effective it is recommended that these streets be fully reconstructed along with installing the necessary utilities. PROPOSED IMPROVEMENTS Existing streets will be reclaimed where pavement thickness is adequate for this process. Reclaiming the streets is a material recycling process where the existing pavement surface and aggregate base layers are pulverized and mixed to form a new aggregate base material. This new homogeneous material is salvaged and reused if testing specifications are met. This process, where applicable, reflects a financial savings to the project since less material must be hauled from and to the site. The top four inches of the aggregate base thickness will require Class 6 aggregate import instead of utilizing reclaim materials to ensure base uniformity for bituminous paving. 3 13