Consider approval of Resolution 2021-225R, approving a Change in Service to the Engineering Services agreement with Halff Associates, Inc. relating to the Blanco Riverine Flood Mitigation Project to advance the project to the bid phase, construction phase, and final close-out services in the estimated amount of $314,181.00; authorizing the City Manager or his designee to execute the appropriate documents to implement the Change in Service; and declaring an effective date.