Integrated Water Resources Plan
Securing Greeley's Water Future
Greeley’s Integrated Water Resource Master Plan (IWRP) provides actionable and adaptive strategies to ensure a resilient and reliable water supply for our community through an uncertain future.
Greeley Water System Overview
Greeley’s raw water supply system is robust and resilient.
Water supplies for our community originate in four river basins on both sides of the Continental Divide. This water is conveyed by river and pipeline, treated at one of two treatment plants, and delivered to our customers.
Once online, the Terry Ranch Aquifer Storage and Recovery Project will add a groundwater supply to the City's water portfolio and provide added resilience against drought and supply variability.
Terry Ranch Project
Terry Ranch consists of 1,200,000 acre-feet of decreed non-tributary groundwater.
- The Terry Ranch project will allow for injection and aquifer storage during times of excess supply. Stored groundwater will be withdrawn during times of drought to satisfy demands.
- Before purchase, a feasibility study was conducted to confirm the safety, reliability, and affordability of the Terry Ranch project. To learn more about the inspection process click HERE
- Until the project is needed, Greeley is investing in additional planning and infrastructure projects to set the foundation for Terry Ranch utilization
When available, treated surface water is injected into the aquifer. During droughts, water is extracted from the aquifer, treated, and delivered to Greeley. Aquifer levels will vary depending on drought conditions; the goal is to keep sufficient water in the aquifer long-term
Greeley's Integrated Water Resources Master Plan (IWRP) is a strategic plan that uses industry best-practices to integrate water supply system planning, from snowmelt to customer taps.
This approach enhances traditional master planning by evaluating how uncertain future conditions could impact Greeley's water supply system.
As part of the IWRP, over 50 water supply risks were analyzed - with the most important being Climate Warming (including increased frequency and severity of wildfire), Colorado River Basin Impacts, Water Rights Challenges, and Demand Growth Uncertainty. Greeley's water originates as snowpack in the Rocky Mountains, and is highly vulnerable to risks such as a warming climate and wild fires.
In 2020 a significant portion of Greeley’s source watersheds were burned in the Cameron Pak and East Troublesome Fires. This highlights the importance of planning for resilience against risks.
Photo credit: Coalition for the Poudre River Watershed
Effects from fire can include severe flooding, erosion and delivery of sediment, nutrients, and contaminants to reservoirs and drinking water facilities. Warmer climates are likely to reduce snowmelt derived water yields and hydrograph shifts may require changes in water rights administration.
Photo credit: Coalition for the Poudre River Watershed
Planning for an Uncertain Future
Due to the uncertainty around what the future could look like, the IWRP used Planning Scenarios to capture a range of future conditions. Scenario planning acknowledges future uncertainty and integrates changes in future conditions through changes in states of drivers. Drivers are the factors that could cause the greatest impact on Greeley’s water resources.
Five future scenarios were used to plan for Greeley’s future in the IWRP. Each scenario paints a picture of what a future may look like, covering possibilities that could look similar to current conditions ranging to conditions that are significantly more stressed or unbearable. This methodology is applied by other water providers in the Front Range and the State Water Plan.
The IWRP uses a planning scenario approach, where varying levels of four drivers including Climate Warming, Colorado River Basin Impacts, water rights administration and demand growth are combined in scenarios that range from “No Climate Change,” to “Optimistic,” to “Continuing Trends,” to “Stressed,” and “unbearable.”
Colorado River Basin Impacts
Colorado River yields are uncertain as drought, administration and compact compliance challenges compound. To capture this uncertainty, a combination of short- and long-term Colorado River yield reductions and curtailments were considered. Notably, the IWRP did not predict how these risks could impact Greeley’s yields but instead included increasingly sever Colorado River impacts.
High Impacts include chronic reduction to Greeley's Colorado River Basin yields and short-term curtailments. Moderate Impacts include curtailments to Greeley's Colorado River Basin Yields. Low Impacts include short-term reductions to Greeley's Colorado River Basin Yields.
Water Rights Administration
Colorado water rights are administered through state water law regulations. Greeley's current and future water yields could be impacted from increasing competition, stricter regulations, or unfavorable legal outcomes.
The IWRP considered two conditions, one where Greeley's water yields are consistent with the recent conditions and another where Greeley's water yields are reduced due to a combination of the above factors.
Demand Growth
The amount of water needed to provide a secure and affordable water supply can differ dramatically depending on how Greeley grows.
Four demand conditions were considered in the IWRP. The conditions differ in four important parameters – the population growth rate, the extent to which irrigation increases in response to hotter and drier future conditions, the extent of future conservation, and the proportion of new housing units that are multifamily apartments and condominiums.
Scenarios
- No Climate Change: Without climate change, Greeley’s water supply system would be less stressed and require less additional water resources.
- Optimistic: Greeley’s water supply system is less stressed than anticipated due to a combination of improved water conservation savings, diminished climate change impacts, and advantageous water rights yields.
- Continuing Trends: Recent trends in per capita water use, climate change, Colorado River basin issues, and competition for water rights continue.
- Stressed: A rapidly warming climate and faster-than-expected population growth within established water providers such as Greeley exacerbates water availability issues. Greeley’s water supply system must meet this increased demand among significant yield impacts.
- Unbearable: Greeley’s future demands have tracked with the most impactful future conditions: population has grown according to the highest forecast, climate has warmed rapidly, and impacts to Greeley’s East Slope water rights and Colorado River supplies are the most severe.
Water Secure Strategies
Greeley's current water supply system is robust and can meet the City's current needs. In the near future, it is resilient to most conditions. However, as we plan for further in the future, additional strategies are needed to ensure sustainable and affordable water supplies. The IWRP identifies several ways to ensure a reliable water supply into the future.
Acquire and Develop water
Greeley will continue to purchase additional water supplies that can be integrated into the current system and the Terry Ranch Project. These additional supplies will help meet demands in the futures with most risk.
Develop Priority Infrastructure
The Terry Ranch Project will be efficiently integrated into Greeley’s water supply system. Greeley will continue to incrementally implementing project components (pipelines, right of way, water rights) to ensure this project is readily available and built with fiscal responsibility in mind.The Terry Ranch Project will be efficiently integrated into Greeley’s water supply system. Greeley will continue to incrementally implementing project components (pipelines, right of way, water rights) to ensure this project is readily available and built with fiscal responsibility in mind.
Invest in Storage & Infrastructure Options
The IWRP identifies storage as an important component of sustainable Terry Ranch operations, which Greeley should further define. In addition, other infrastructure projects that improve the efficiency and operations of the existing system should be completed.
Water Efficiency & Demand management
Greeley will continue to invest in non-potable water and efficiency programs. Efficiency programs will be aimed at addressing environmental justice goals and provide sustainable landscapes for the entire community
Adaptive Management
The IWRP found that Greeley’s current water supply system is robust under near term future conditions and that the Terry Ranch project provides drought resilient long-term water supply. Moving forward, continued Adaptive Planning to regularly evaluate and update IWRP outcomes will ensure Greeley continues to provide sustainable water supplies.
Adaptive planning recognizes that changes will occur before the next plan update and establishes a process to monitor and respond to those changes. Five actions were defined for staff to take each year to monitor and respond to changing conditions.
The following five adaptive plan actions are completed each year:
Monitor Demand Growth and Water Supply Conditions: Greely staff will review trends in water demands and supply conditions. Areas of interest to monitor conditions are at the State, Local and City level as well as within Greeley's source water basins.
Evaluate Terry Ranch Triggers: In order to confidently time implementation of Terry Ranch, the Adaptive Plan will compare demand indicators to supply indicators and trigger potential actions as a result.
Update Terry Ranch Implementation Plan: Annual updates to on Greeley's 5 and 10-year strategy for Terry Ranch integration will include infrastructure and financing.
Assess Water Right Changes & Acquisitions: The Adaptive Plan will assess how water rights changes and acquisitions are progressing compared to the IWRP goals and if changes are required.
Review Other Water Supply Opportunities: Greeley will continue to invest in a variety of projects that improve the water supply system such as the non-potable system, conservation, and smaller-scale infrastructure projects. Status updates of these projects, such as function, schedule, and budget will be provided in the Adaptive Plan.