Colorado Public Works Journal, Summer 2023

66┃ Colorado Public Works Journal Mike Skinner is the Director of Pavement Engineering for the Colorado Asphalt Pavement Association. He can be contacted at CAPA Mike Skinner The Colorado Front Range has had a rough start to the 2023 paving season. According to the National Weather Service in Boulder, this has been the second wettest start to summer in Denver on record dating back to 1876. Rainfall analysis for the period from May 1st to June 17th shows accumulations over 15” over the Palmer Divide. The Denver weather station historically reports 4” of rain over that period, however, this year Denver has seen over 10.8” of rain over the last six weeks. This unusual amount of heavy rain has created significant impacts on the construction schedule of asphalt paving projects. The excessive rainfall has caused delays and disruptions at various stages of the construction process. Firstly, heavy rain can make the ground too wet and muddy, making it unsuitable for the placement of the asphalt pavement. The wet conditions can prevent proper compaction, resulting in a weaker and less durable surface. Additionally, rainwater can create potholes and depressions, making it necessary to repair or rework certain areas before proceeding with the paving. These delays can extend the overall project timeline, causing frustration for both contractors and project owners. However, one advantage of asphalt paving is its inherent flexibility, allowing for adjustments to accommodate weather-related setbacks. Asphalt can be laid in multiple layers, allowing for adjustments in the construction process to account for delays caused by heavy rain. Moreover, project managers can allocate additional resources and adjust work schedules to make up for Spring and Summer Heavy Rain Impacting Project lost time, thus maintaining the project’s completion within the desired timeframe. This flexibility in asphalt paving construction allows for adaptability to weather conditions and helps mitigate the impacts of heavy rain on project schedules. BEST PRACTICE for CONTRACTORS, OWNERS and LOCAL AGENCIES When project schedules are impacted by significant weather, Best Practice for Project Delivery is to exercise maximum flexibility to complete the work; • Extend project working hours. • Negotiate schedule milestones. • Appropriately incorporate weather delay days as provided in the contract. To help analyze the impacts of rainfall to Project Delivery, CAPA has developed the ‘Rainfall Impacts to Project Delivery’ Tool, including: • Accumulation Data. This tool provides fully customizable rainfall accumulation data in numerical and graphical form. Customizable dates allow for analysis for specific contract begin/end dates or seasonal analysis. •Rainfall Map. This tool creates customizable rainfall accumulation maps. This free tool is available from CAPA, contact Mike Skinner (Director of Engineering) at for a copy.