AGENDA CAPTION:
Title
Consider approval of Resolution 2018-91R, approving the award of an Engineering Contract to Lockwood, Andrews & Newnam, Inc., for the Purgatory Creek project, in the estimated amount of $467,440; authorizing the City Manager or his designee to execute the said agreement on behalf of the City; and declaring an effective date.
Body
Meeting date: 6/5/2018
Department: Engineering & CIP
Amount & Source of Funding
Funds Required: $467,400
Account Number: C679
Funds Available: $500,000
Account Name: Purgatory Creek Improvements
Fiscal Note:
Prior Council Action: NA
City Council Goal: [Please select goal from dropdown menu below]
Goal #5 Maintain & Improve City's Infrastructure
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Comprehensive Plan Element (s): [Please select the Plan element(s) and Goal # from dropdown menu below]
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☒ Land Use - Direct Growth, Compatible with Surrounding Uses
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☒ Not Applicable
Master Plan: [Please select the corresponding Master Plan from the dropdown menu below (if applicable)]
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Background Information:
The work to be performed will consist of developing preliminary designs to improve existing flooding conditions for approximately 6,100 linear feet along Purgatory Creek from South Mitchell Avenue to the San Marcos River. The Preliminary Engineering Report (PER) results will provide conceptual options to reduce the water surface elevations and improve water quality and current erosion and sedimentation issues to support outside funding requirements The limits of the study extend from NRCS Dam No. 5 to the San Marcos River. The improvements to be evaluated include:
• Bridge/culvert modifications or replacements at Mitchell Avenue, Jackman Street, Guadalupe Street, South LBJ Street, CM Allen Parkway and Comal Street.
• Curb cuts along Mitchell Avenue.
• Extension of storm drains near South LBJ and Cheatham Street and the 100 block of Edward Gary Street.
• Channel improvements.
• Replacement of wastewater main along Jackman Street from Valley Street to Gravel Street, along Gravel Street from Jackman Street to Patton Street and along Patton Street to the railroad.
• Mill and overlay of street pavement impacted by proposed improvements
• Sidewalk improvements including new sidewalks along S. Mitchell Avenue and Gravel Street.
The Purgatory Creek watershed has had a history of previous flooding during various storm events. This project will develop improvements that result in a reduction to flooding conditions, improvement to water quality and greenway connectivity as identified in the Transportation Mater Plan.
The Purgatory Creek Improvement project will be conducted in phases with the first phase consisting of a preliminary engineering evaluation and preparing a PER. During the PER phase we will evaluate the Purgatory Creek watershed and develop recommended improvements that result in a reduction of existing flooding conditions and improve water quality. Proposed improvements will consider channel modifications, bridge/culvert modifications or replacements, and storm drain modifications.
The PER phase will include conducting public meetings to solicit citizen comments regarding flooding concerns and ideas regarding improvements. The project will also include conducting a hydraulic analysis considering previous developed hydraulic models for the watershed and new 2D analysis models to reflect conditions at and near the confluence of Purgatory Creek and the diversion to Willow Springs Creek. The hydraulic models will also reflect proposed improvements and determine impacts to the 25- and 100-year storm events considered to be effective by FEMA. The PER phase will also include determining right-of--way and easement requirements, identifying potential impacts between existing utilities and proposed improvements, environmental and permitting requirements, and developing preliminary probable cost to construct proposed improvements.
The PER will be completed within 8 months including time for City review of submittals.
Council Committee, Board/Commission Action:
NA
Alternatives:
NA
Recommendation:
Staff recommends approval of design contract