7.6.
CC Regular Session
- Meeting Date:
- 05/23/2017
- By:
- Bruce Westby, Engineering/Public Works
Information
Title:
Adopt Resolution #17-05-121 Accepting Quotes and Awarding Contract for Improvement Project #17-11, Ground Penetrating Radar Pavement Evaluations - 2018 & 2019 Reconstruction and Overlay Improvements
Purpose/Background:
Purpose
The purpose of this case is adopt Resolution #17-05-121 accepting quotes and awarding a contract for Improvement Project #17-11, Ground Penetrating Radar Pavement Evaluations for 2017 - 2026 CIP Reconstruction and Overlay Improvements
Background:
On more than one occasion staff has proposed pavement maintenance improvements to existing streets based on pavement section information found in plans or by examining spot locations of the existing pavement section, only to learn at a later date that the pavement section was not constructed per plan, or that the pavement section was not consistent throughout. The proposed design must then be revised, which in turn delays projects and impacts project costs, as well as proposed assessment amounts.
This happened most recently in the Rivers Bend development where a mill and overlay project was proposed for 2017. After soil borings and pavement corings were completed, it was discovered that the pavement was too thin to effectively mill and overlay so the street had to be rescheduled for a reconstruction in 2018.
Staff researched available options for evaluating existing pavement section structures and determined that two primary options exist. Staff have typically used soil borings or pavement corings in the past to verify existing pavement sections at numerous locations along street segments. However, a newer technology has emerged in the form of ground penetrating radar. Of these two methods, the ground penetrating radar is significantly cheaper.
Ground penetrating radar has been used primarily to locate items buried underground. However, this technology is now being used to evaluate the existing pavement section design in 1 to 2 foot intervals along the entire street, depending on the speed at which the vehicle the radar unit is attached to is traveling. The radar is strong enough to penetrate the top foot or so of the pavement section, revealing changes in material densities between the bituminous or concrete pavement section, the aggregate base section, and subgrade soils. A minimal number of pavement cores are also extracted to calibrate the readings and to verify the specific pavement and aggregate base materials, as well as the subgrade soils.
The City has never used ground penetrating radar to evaluate existing pavement sections, whereas soil borings and pavement corings have been used extensively for this purpose. However, staff has found that existing pavement sections on older City streets can vary significantly from location to location. Staff therefore proposes to use ground penetrating radar to evaluate existing pavement sections on all streets proposed to be reconstructed or milled and overlaid per the 2017 - 2026 CIP.
Staff identified two companies that provide ground penetrating radar services for the purpose of evaluating pavement sections; Braun Intertec Corporation and American Engineering Testing, Inc. Requests for Proposals were submitted to both companies on May 5th, and both firms submitted proposals on May 16th. Due to staff’s unfamiliarity with this technology the proposals broke costs out into two phases. Phase 1 includes 9.2 miles of streets proposed to be reconstructed and/or milled and overlaid in 2018 and 2019, the last 2 years remaining in the current 5-year Street Reconstruction and Overlay Program bond issue. Phase 2 includes 23.5 miles of streets proposed to be reconstructed and/or milled and overlaid from 2020 to 2024, the next 5 years in the current 10-year CIP.
Quotes received from each firm for the Phase 1 and Phase 2 evaluations are shown below.
Braun Intertec’s total quote for both phases is the lowest. Based on the submitted quotes staff recommends proceeding with both phases of pavement evaluations as this will allow the City to most cost-effectively evaluate the existing pavement sections of all streets identified for street reconstruction and mill & overlay improvements in the 2017 – 2026 Capital Improvement Program. This will benefit the City significantly by verifying the existing pavement section designs on all proposed street reconstruction and mill & overlay improvements proposed over the next 10 years.
The Contractor is required to maintain minimum insurance coverages, and all work shall be carried out during normal working hours from 7:00 a.m. to 10:00 p.m., Monday through Saturday, in accordance with City ordinances.
The Contractor shall complete their work by August 11, 2017, which will allow staff to complete Feasibility Reports for all 2018 street reconstruction and mill and overlay projects by September so plans can be prepared and bids can be solicited for this work in a timely manner.
The purpose of this case is adopt Resolution #17-05-121 accepting quotes and awarding a contract for Improvement Project #17-11, Ground Penetrating Radar Pavement Evaluations for 2017 - 2026 CIP Reconstruction and Overlay Improvements
Background:
On more than one occasion staff has proposed pavement maintenance improvements to existing streets based on pavement section information found in plans or by examining spot locations of the existing pavement section, only to learn at a later date that the pavement section was not constructed per plan, or that the pavement section was not consistent throughout. The proposed design must then be revised, which in turn delays projects and impacts project costs, as well as proposed assessment amounts.
This happened most recently in the Rivers Bend development where a mill and overlay project was proposed for 2017. After soil borings and pavement corings were completed, it was discovered that the pavement was too thin to effectively mill and overlay so the street had to be rescheduled for a reconstruction in 2018.
Staff researched available options for evaluating existing pavement section structures and determined that two primary options exist. Staff have typically used soil borings or pavement corings in the past to verify existing pavement sections at numerous locations along street segments. However, a newer technology has emerged in the form of ground penetrating radar. Of these two methods, the ground penetrating radar is significantly cheaper.
Ground penetrating radar has been used primarily to locate items buried underground. However, this technology is now being used to evaluate the existing pavement section design in 1 to 2 foot intervals along the entire street, depending on the speed at which the vehicle the radar unit is attached to is traveling. The radar is strong enough to penetrate the top foot or so of the pavement section, revealing changes in material densities between the bituminous or concrete pavement section, the aggregate base section, and subgrade soils. A minimal number of pavement cores are also extracted to calibrate the readings and to verify the specific pavement and aggregate base materials, as well as the subgrade soils.
The City has never used ground penetrating radar to evaluate existing pavement sections, whereas soil borings and pavement corings have been used extensively for this purpose. However, staff has found that existing pavement sections on older City streets can vary significantly from location to location. Staff therefore proposes to use ground penetrating radar to evaluate existing pavement sections on all streets proposed to be reconstructed or milled and overlaid per the 2017 - 2026 CIP.
Staff identified two companies that provide ground penetrating radar services for the purpose of evaluating pavement sections; Braun Intertec Corporation and American Engineering Testing, Inc. Requests for Proposals were submitted to both companies on May 5th, and both firms submitted proposals on May 16th. Due to staff’s unfamiliarity with this technology the proposals broke costs out into two phases. Phase 1 includes 9.2 miles of streets proposed to be reconstructed and/or milled and overlaid in 2018 and 2019, the last 2 years remaining in the current 5-year Street Reconstruction and Overlay Program bond issue. Phase 2 includes 23.5 miles of streets proposed to be reconstructed and/or milled and overlaid from 2020 to 2024, the next 5 years in the current 10-year CIP.
Quotes received from each firm for the Phase 1 and Phase 2 evaluations are shown below.
| Contractor | Phase 1 Quote | Phase 2 Quote | Total Quote |
| Braun Intertec Corp. | $7,795 | $10,290 | $18,085 |
| American Engineering Testing, Inc. | $7,450 | $15,800 | $23,250 |
Braun Intertec’s total quote for both phases is the lowest. Based on the submitted quotes staff recommends proceeding with both phases of pavement evaluations as this will allow the City to most cost-effectively evaluate the existing pavement sections of all streets identified for street reconstruction and mill & overlay improvements in the 2017 – 2026 Capital Improvement Program. This will benefit the City significantly by verifying the existing pavement section designs on all proposed street reconstruction and mill & overlay improvements proposed over the next 10 years.
The Contractor is required to maintain minimum insurance coverages, and all work shall be carried out during normal working hours from 7:00 a.m. to 10:00 p.m., Monday through Saturday, in accordance with City ordinances.
The Contractor shall complete their work by August 11, 2017, which will allow staff to complete Feasibility Reports for all 2018 street reconstruction and mill and overlay projects by September so plans can be prepared and bids can be solicited for this work in a timely manner.
Notification:
No notifications are required with this case.
Observations/Alternatives:
Alternative #1 - Motion to adopt Resolution #17-05-121 accepting quotes and awarding a contract for Improvement Project #17-11, Ground Penetrating Radar Pavement Evaluations for 2017 - 2026 CIP Reconstruction and Overlay Improvements.
Alternative #2 - Motion denying adoption of Resolution #17-05-121 at this time.
Alternative #2 - Motion denying adoption of Resolution #17-05-121 at this time.
Funding Source:
Funding for this work is proposed to come from the $500,000 budgeted for annual street Crackseal and sealcoat improvements. On May 16th, the Public Works Committee recommended City Council approval of using up to $35,000 of this budget amount for this purpose.
Recommendation:
City staff recommends Alternative #1.
Action:
Adopt Resolution #17-05-121 accepting quotes and awarding a contract for Improvement Project #17-11, Ground Penetrating Radar Pavement Evaluations for 2017 - 2026 CIP Reconstruction and Overlay Improvements.
Attachments
Form Review
| Inbox | Reviewed By | Date |
|---|---|---|
| Kurt Ulrich | Jo Thieling | 05/18/2017 03:21 PM |
- Form Started By:
- Bruce Westby
- Started On:
- 05/16/2017 08:05 AM
- Final Approval Date:
- 05/18/2017