Reviving a Watershed

Protecting water quality, restoring beaver habitat and building resilience to wildfires and floods on the Upper River Poudre Watershed

Project information
  • Management Plan
  • Total budget: £40,000
  • Budget spent: £18,412
  • Status: In Progress

The Cache la Poudre River is a vital watercourse originating from Rocky Mountain National Park and flowing through northern Colorado. This river and its tributaries support a rich diversity of wildlife and provide vital resources for the surrounding communities. However, recent wildfires and historical land use have significantly degraded parts of the river, threatening water quality and habitat integrity.

In partnership with the Coalition for the Poudre River Watershed, we are focusing on restoring riverine and wetland functions in landscape 'pearls' - priority areas of the watershed. Through interventions such as installing low-tech process-based structures and engaging key stakeholder and community groups, this project aims to achieve a myriad of benefits: reduced sedimentation; protected water quality; strengthened resilience to floods and wildfires; and improved ecosystem connectivity and health.

Project Timeline

The Cache la Poudre River Watershed

The Cache la Poudre River, generally known as the “Poudre,” is part of the South Platte River basin. The Poudre spans approximately 140 miles and serves around 300,000 people in northern Colorado. The river originates in Rocky Mountain National Park and flows through the Roosevelt National Forest, eventually passing through Fort Collins and joining the South Platte River near Greeley.

The upper reaches of the Poudre are designated as “Wild & Scenic,” providing important recreational opportunities and supporting a range of wildlife.

The Poudre River and its tributaries are a network of waterways that provide habitat for fish, plants and insects that include grasses, rushes, and sedges as well as shrubs and trees that grow along its banks.

Areal shot of a meander in the South Fork of the Poudre River (Photo credit: Ayres Associates)
The Upper River Poudre Watershed (Photo credit: Ayres Associates)

The Riparian Ecosystem

The rich riparian ecosystems along the Poudre River host a diverse array of biodiversity and support numerous natural processes and functions. This vibrant water course provides essential habitats for a variety of insects, amphibians, fish, and other species, including the threatened Preble’s Meadow Jumping Mouse, wood frogs, and potentially the Boreal Toad. The natural vegetation, including cottonwoods, aspens and native willows, are essential for providing food, shelter and breeding grounds for these species.

Healthy riparian zones also play a crucial role in mitigating flooding, helping to maintain water quality and stabilising stream banks. In addition, trees and vegetation along the riverbanks create shade, which in turn helps control water temperatures, prevents erosion of their root systems and contributes to organic material that supports aquatic life. Maintaining an ideal balance of shade and sunlight is essential in sustaining healthy aquatic plant life and overall ecosystem health.

a meander drone shot of the river poudre
A bird's eye view of South Fork, one of the intervention areas.

A Degraded Habitat

The Poudre River faces significant challenges due to physical alterations, pollution, and sedimentation from surrounding land use. Agricultural runoff, livestock access and historical land management practices have led to habitat degradation. Besides this, the widespread removal of beavers from many of these streams has led to a loss in their function to store sediment, reduce flood and fire risk, and support adequate wildlife.

Wildfires, such as the 2012 High Park and 2020 Cameron Peak fires, have further exacerbated these issues, causing erosion, debris flows and deteriorating water quality. These factors collectively threaten the overall resilience of the riparian ecosystems.

High Park Wildfire on the Arapaho and Roosevelt National Forests and Pawnee National Grassland on Thursday, June 17, 2012. (Photo credit: US Dept. of Agriculture)
High Park Wildfire on the Arapaho and Roosevelt National Forests and Pawnee National Grassland on Thursday, June 17, 2012. (Photo credit: US Dept. of Agriculture)

Removal of the Beaver, a Keystone Species

Ecological powerhouse

The beaver (Castor canadensis) is a keystone species that plays a vital role in maintaining the ecological health and biodiversity of the Poudre River. Through their dam-building activities, they create and enhance wetland habitats, which many other species rely on. Their presence transforms river and stream habitats into varied, rich environments that support numerous insects, amphibians, fish, and other wildlife. Additionally, beaver activity helps stabilise stream banks, reduce erosion, and improve water quality by trapping sediments and pollutants.

Furthermore, the wetlands created by beaver dams are significant in mitigating flooding by slowing down water flow and increasing groundwater recharge. By maintaining these dynamic habitats, beavers enhance the resilience of the Poudre River ecosystem to changes, such as the impacts of climate change.

Beaver declines

The historical decline of beaver populations due to hunting and habitat destruction has led to profound ecological consequences. In North America, estimates say that beaver populations have declined by 80% to 98% since pre-European settlement, compounding issues such as increased erosion, degraded water quality and loss of habitat diversity.

Despite their ecological importance, Colorado state law allows for beavers to be hunted and killed if they damage property. This legal framework creates a conflict between human interests and ecological preservation, highlighting the need for policies that balance property protection with the conservation of essential species.

a beaver on grasslands
The beaver is a keystone species and its presence or absence in riparian ecosystems is profound.

Our Project

The primary objective of this project is to restore sections (both burnt and unburnt) of the Cache la Poudre River and its tributaries, such as Elkhorn Creek and South Lone Pine, to improve ecological health and habitat connectivity.

Project interventions:

  1. Installation of LTPBR structures: Use Low-Tech Process-Based Restoration (LTPBR) structures, such as post-assisted log structures and beaver dam analogues, to enhance water flow diversity, create new wetland areas and provide habitat complexity.
  2. Livestock management: Implement livestock fencing (if needed) and create buffer strips to reduce encroachment along the tributaries.
  3. Riparian tree management and planting: Planting native willow and cottonwood trees to regulate water temperatures and stabilise banks, to help restore the riparian habitat.
Beginning of works to install the first LTPB structures (Beaver Damn analogues) in South Fork
The beginning of work to install the first LTPB structures (Beaver Dam Analogues) in South Fork.

Desired Outcomes

Short-term:

  • Enhanced habitat diversity and complexity
  • Improved sediment storage potential as LTPBR structures capture sediment

Medium-term:

  • Improved water quality as riparian and wetland ecosystems help to filter pollutants and trap sediment
  • Increased resilience to severe wildfires and flooding
  • A more engaged community that is aware of the benefits of this type of restoration and the conservation/enhancement of wetlands and riparian areas

Long-term:

  • Sustained health and resilience of riparian and wetland ecosystems which will contribute to the overall health of the watershed. Beavers would come back into the system and build off the installed structures and maintaining the ecological integrity of the site(s)

This project aims to serve as a flagship restoration effort, inspiring public interest and contributing to the long-term health and resilience of the Cache la Poudre River and its watershed. By addressing critical threats and implementing targeted restoration efforts in partnership with the Coalition for the Poudre River Watershed (CPRW), we aim to create a healthier, more resilient Poudre River ecosystem that benefits both wildlife and the surrounding communities for generations to come.

the team installing fake beaver dams
Installing beaver dam analogues will help reduce sedimentation and filter pollutants.
the Coalition for the Poudre River Watershed team installing fake beaver dams

Community & Stakeholder Engagement

Community and key stakeholder involvement is an important component of this project, which will influence buy-in from land managers, private landowners and the local community. There are several priority areas located on private land and the concepts behind low-tech process-based restoration are still relatively new to some land managers and private landowners in the watershed, so the data and experience with completing these projects will need to be shared widely.

Ways in which this project aims to create engagement, include:

  • Collaborating with CSU researchers and community scientists in data collection on water quality and pre and post project monitoring via photo points, cross sections and vegetation surveys.
  • Organising regular meetings with private landowners and local community members to update on the project's progress. Additionally, CPRW will meet with local road association in the project area to share project plans and updates.
  • Running tours at similar projects completed in 2021-2023 to showcase examples of low-tech process-based restoration 1-2 years after construction.
  • Engaging with the local press from local news sources like the Fort Collins Coloradoan & North Forty News to CBS and/or 9News in Denver, Co.

The work of CPRW is under the guidance of the Upper Poudre Stakeholder Committee, which meets quarterly and includes representatives from the US Forest Service, Colorado State Forest Service, Colorado Parks and Wildlife, local municipalities, county government, researchers, landowners, and non-profit organisations.

CPRW members in discussion
Collaboration and communication is a vital part of the long-term success of this project.

Project discussion

Heart Image

the team behind the project

Team Member

Flora Hentz, Partnership Project Coordinator, Mossy Earth

Team Member

Hally Strevey, Executive Director, Coalition for the Poudre River Watershed

Coalition for the Poudre River Watershed logo
fake beaver dam on the poudre watershed

Sources & further reading

Peer Reviewed Research Section
  1. Photo credits: Ayres Associates, CPRW & Mike Laughlin