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another temporary repair, unlikely to last much longer than prior attempts at repairs. A long-term solution is necessary, requiring reconstruction of several sections of the roadway. Long -Term Solution Engineering will begin a request for qualifications process to find a qualified consultant team to investigate the settlement and develop a repair recommendation that can be used to prepare plans and specifications for the permanent repair of West Las Positas Boulevard between Hopyard Road and Stoneridge Drive. A consultant contract will be brought back to City Council for award upon selection. The permanent repair and reconstruction will need to be cognizant of the recommended bike and pedestrian improvements currently under development by the Traffic Division. It is anticipated that the long-term repair will require the entire roadway section, including the subgrade, to be removed, perhaps up to 4 feet below the base, and be replaced with an engineered roadway fill material. The road base and asphalt layers will then be installed over the engineered fill. The roadway will then "bridge" over the deeper clay soils which should maintain a relatively consistent moisture content and not experience the same differential settlements that are currently observed. This will most likely require all existing curb and gutters, landscaping and adjacent sidewalks to be removed and replaced in the settled areas. It is also anticipated that some of the utilities will require repair and replacement to address possible settled locations as the roadway is reconstructed. As part of the study phase, a detailed condition assessment will be completed on the utilities to ensure that the utilities will not require replacement in the near future after the roadway reconstruction, as excavations for repair of utilities may impact the engineered fill section. It is also anticipated that the roadway repair strategy selected will be fairly prescriptive on how to backfill the utility excavations that will eventually occur in the future. The roadway reconstruction costs will not be fully known until the repair strategy is selected and the final roadway cross section is identified. However, West Las Positas Boulevard from Hopyard Road to Stoneridge Drive is approximately 6,000 feet in length, with a paved roadway surface of approximately 470,000 square feet. Conventional pavement reconstruction runs between $8-$10 per square foot, and it is anticipated the engineered fill restoration could run as high as $10-$15 per square foot. While it is not anticipated that the entire street will require restoration to a depth of four feet, it is estimated the cost of pavement restoration could be between $6-$8 million. This does not include curb and gutter, sidewalk, landscaping or utility work. If a complete streetscape, replacing all surface improvements within the right-of-way, including all landscaped areas is required, the costs could exceed $10 million. These figures are provided as an order of magnitude for the street restoration. They will be refined during the geotechnical and utility investigations. Schedule Temporary repairs of the roadway will be completed by November 2020. The recommendation of the consultant design team to analyze permanent repair options Page 5 of 6