27th Avenue Stormwater Project

There is an urgent need to improve the stormwater system along 27th Avenue to prevent annual flooding. This will be a four year project, beginning July 2015 with a segment of 27th Avenue from 16th Street to 17th Street Road. Construction will be complete before the end of the ​2015, after which design will begin for the next phase. Phases II through IV will carry the improvements north to the Poudre River over the next four years.


27th Ave Phase 1 Schedule

Construction Update July 22, 2016

The second half of our construction project near 28th Avenue and 17th Street is underway. We’re placing slightly smaller box culvert pipes than last fall, but they still weigh about 40,000 pounds! In the interest of safely, we’ve closed 28th Ave until about August 10. Our crews are working as fast as they can to get that road back open. In the meantime, please be safe and follow all detour signs. They’ve already started placing these boxes in 17th Street Road. Then they’ll be placing inlets in 17th Street, 17th Street Road and finally 16th Street.

Project details

Why do we need this project?

High water markThis picture shows the high water mark of stormwater on a patio door after approximately three inches of rain fell on August 6, 2008. This home on 28th Avenue is among several in the basin that experience damage during larger storm events. The 28th Avenue Drainage Basin is about four square miles running north to the Poudre River and situated west of downtown. Water at the house and other locations was measured at 18” deep. Based on historical data, there is about a 10-50% chance that the storm from 2008 could occur in any given year.

How will this project help?

Currently, the 28th Avenue Drainage Basin does not have enough storage space for larger rain events and the pipes are generally undersized. The water wants to find an easy path, which sometimes ends up being into a basement. In other areas of town, where there is vacant land, a pond could be built to provide storage, or detention, to reduce the flooding. Here there is not enough land available so concrete boxes under the streets will be used as a path for the water and also for storage. These boxes are much larger and will carry much more water than the existing pipes in the area.

What Work is Being Done?

27th Avenue Project detailPhase I will begin by relocating some of the existing utilities such as water and sewer lines to make room for the concrete boxes. The boxes and all of their associated parts will then be installed. Some of these parts will include new inlets so that more water will reach the boxes and less will be standing in the streets. Lastly, the streets will be restored and new asphalt placed to create a smooth driving surface. The sketch shows a cross-section of what will be underneath the street when it’s all finished.

When and Where? 

Phase 1 Construction

Construction in the Phase I area will begin in August of 2015 and will be partially complete by December 1st. The remainder will be done next spring, about the same time as construction of Phase II is scheduled to start. Phase II will include work in the Woodbriar Park/19th Street Area. Phase III will continue the project northward along 27th and 26th Avenues, the timeline for this is approximately 2-3 years from now. After that, Phase IV will see improvements in the #3 Ditch and northerly channel all the way to the Poudre River.

27th Avenue Phasing | PDF 1MB


  • What’s being done? Why?

    • The City has designed a new stormwater system to replace the current pipes which are too small to handle larger rainfall events. Construction involves moving some existing utilities and placing large concrete boxes and inlets under the streets to collect and carry stormwater. This is a continuation of the first phase to improve conditions in the entire area.
  • When will construction start?

    • Construction and impacts to traffic began in July.
  • How long is construction going to last?

    • Phase I should be complete by November 20.
  • Will there be detours? Will 16th Street be closed? What about 28th Avenue?

    • From July 19th through approximately Aug 12th, 28th Avenue will be closed to through traffic. Residents of the immediate area will be allowed access, all other traffic should follow the detour signs and use 16th Street, 23rd Avenue, 20th Street or 35th Avenue as shown in the map below. 16th Street will have one eastbound lane closed between approximately October 10th and November 20.
      Detour Mapclick image to enlarge
  • Who do I call if there are problems?

    • Please feel free to contact the Project Manager Bert Leautaud, PE at 970-336-4121 or Bert.Leautaud@greeleygov.com with questions or concerns.
  • Will this stop the flooding problems?

    • Phase I is a great first step in alleviating the flooding in this area. When the following phases are constructed, the system in this area will be able to handle 90% of probable storm events.
  • What happens next?

    • Construction of Phase II is scheduled to begin in the Fall of 2016, and continue through 2017.
  • Will my stormwater bill be affected?

    • This project is being funded by your Stormwater Fees; they will not be increased to pay for this work. Any possible future increases would be City wide and funds would be used for the entire Stormwater Program, not specifically for this project.

Contact Us

Bert Leautaud, PE, Project Manager

Public Works | Stormwater


Keep Greeley Moving

Stay informed!

Lane changes and detours will be posted as necessary. If you would like to receive email updates regarding this project, send your email address to streetstuff@greeleygov.com.