Site work and paving for a road / highway in Walnut Creek, California. Working plans call for site work for a road / highway; and for paving for a road / highway.

The Contra Costa Transportation Authority (Authority) is seeking proposals from qualified consultants to provide Pre-Construction and Construction Management Services for the I-680/SR4 Interchange Improvement Project Phases 2A (CM Optional) and 4. The contract will have two task orders: o Task 1: Provide Pre-Construction Services for Phases 2A and 4. o Task 2: Provide Construction Management Services for Phase 4 with an option for Phase 2A. Online Q&A Yes Q&A Deadline 01/22/2025 5:00 PM (PST) Phase 2A: Phase 4: RFP No. 24-10 Contra Costa Transportation Authority Page 1 In cooperation with the California Department of Transportation (Caltrans), the Authority proposes the 1-680/SR 4 Interchange Improvements Project which would improve the operational efficiency of the interchange, reduce traffic congestion and delays, improve safety, eliminate short weaving and merging sections, and provide direct access between 1-680 and Pacheco Boulevard. The project has been divided into five stages with Phase 3 being the only phase completed to date. Phases 2A and 4 are described as follows: Construct a two-lane direct connector from SB 1-680 to EB SR 4 Realign northern portion of SB 1-680 to WB SR 4 diagonal ramp Remove existing loop ramp from SB 1-680 to EB SR 4 Construct auxiliary lane along EB SR 4 from the entrance of the direct connector stated above to 1,000 feet north of Peralta Road Along EB SR 4, realign Solano Way off-ramp and on-ramp to accommodate above mentioned auxiliary lane Remove the Collector-Distributor (C-D) road parallel to SB 1-680 and realign entrance of loop ramp from WB SR 4 to SB 1-680 Widen southern portion of diagonal ramp from NB 1-680 to EB SR 4 from 1 to 2 lanes Install ramp metering facility for SB 680/EB SR 4 on-ramp PRE-CONSTRUCTION AND CONSTRUCTION MANAGEMENT SERVICES FOR INTERSTATE 680/STATE ROUTE 4 INTERCHANGE IMPROVEMENTS PHASES 2A (CM OPTIONAL) AND 4 Widen diagonal ramp from EB SR 4 to SB 1-680 from 1 to 2 lanes. Widen portion of loop ramp from WB SR 4 to SB 1-680 from 1 to 2 lanes. This will require widening the existing bridge over Grayson Creek Bridge. Construct auxiliary lanes as follows: o Along SB 1-680 from the EB SR 4 to SB 1-680 to the 300 feet to the north of Center Avenue Install ramp metering facility for SB 1-680 on-ramp The estimated construction cost for Phases 2A and 4 is approximately $173.5 Million.