Agenda - Public Works Committee - 04/16/2024

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4.0 DISCUSSION AND RECOMMENDATIONS 4.1 Proposed Construction This project will include improving the several streets within 3 areas of the City of Ramsey. Based on the RFP we understand that street improvements will include reconstructing the existing roadways. Reconstruction could include completely removing and replacing the existing pavements or a full -depth reclamation. We further understand that no sanitary sewer or watermain utilities are planned at this time. However, we anticipate that culvert and/or storm sewer installation or replacement could will likely be included in the project. We anticipate that site grading will consist of earthwork necessary for and roadway reconstruction and culvert/storm sewer replacements, if any. We do not anticipate any significant changes in the roadway alignment or roadway grades. Cuts or fills involving permanent grade change, if any, are assumed to be less than 1 feet. Invert elevations or pipe burial depths for any storm sewer and/or culvert installation are anticipated to be on the order of 5 feet. We were not provided any information regarding traffic volumes such as Average Annual Daily Traffic (AADT) counts or vehicle distribution for the roadways. We assumed these roadways will be utilized mainly by automobiles, light trucks and school buses with weekly use by heavier vehicles such as garbage trucks and UPS or FedEx type delivery vehicles. In accordance with the RFP the streets will be reconstructed as a 9-ton street and designed as a low volume (local) road. Based on that we estimate that the streets will be subjected to Equivalent Single Axle Loads (EASL's) significantly less than 50,000 over a design life of 20 years. Changes in the nature, design, or location of all or parts of this project may occur. Likewise, if the proposed traffic volumes exceed these values we should be informed. Additional analyses and revised recommendations may be necessary. 4.2 Discussion Pavements We were not provided any information regarding the age of the existing pavement but based on a brief review of historical aerial photographs available on Google Earth it appears that the streets were constructed prior to 2000 and likely prior to 1991. Based on that we assume the pavement are at least 23 years old and are likely older. Some of the cores basically disintegrated while coring. The pavement cores appeared to be brittle (i.e., oxidized). The binder oils and bitumen within the pavements appears to have degraded over time. It appears that the streets have been maintained as evidenced by seal coating and crack sealing/crack repairs observed along the alignments while drilling. Given the estimated age of the pavements it appears the pavements have generally performed as designed and based on an assumed 20-year service life, the pavements appear to have significantly exceeded their intended design life. We observed longitudinal and transvers cracks with some "alligator' or fatigue cracking of the pavement surfaces. The cracking observed could be the result of a combination of factors including; inadequate pavement thickness, pavement age and possibly frost action/frost heave. i