How does the Steamboat Segment score?

Despite having several small reservoirs upstream, the Yampa River is notable for its managed flow system that preserves natural peak flows and mimics a typical, unaltered river flow pattern. This careful human management ensures that, unlike many rivers altered by human structures, the Yampa retains characteristics of a natural, free-flowing river. The Yampa’s natural flow pattern supports a diverse and vibrant ecosystem, playing a crucial role in sustaining local flora and fauna.

It’s complicated…

Multifaceted challenges that threaten the Yampa’s vitality include potential future declines in water flow due to factors like climate variability, changing precipitation patterns, and increasing water consumption needs. An example of this is that although peak flows are maintained to closely mimic the natural hydrograph, flows during low flow periods (fall and winter) have been declining. Summer low flows also contribute to water quality concerns, particularly temperature. Other risks such as pollution, habitat disruption, and invasive species also loom over the river’s health.

Rivers are naturally dynamic and bank stabilization efforts can often push the problem downstream.

For a deeper understanding of the energy of the river, click on the indicator.

The Yampa River’s health is closely linked to its water temperature, yet all reaches in the Steamboat segment are on the State’s 303(d) impaired waterbody list for temperature. This designation highlights the impacts of elevated temperatures on the river’s ecosystem, including altered water chemistry, algal blooms, and reduced dissolved oxygen. Key sources of warming in the Yampa River include reservoirs like Lake Catamount, which can release warmer water than the Yampa inflows by late summer, and water diversions that reduce flow resulting in warmer temperatures. The removal of riparian vegetation due to land use changes and the impacts of climate change further contribute to this warming trend, especially during low flows. These conditions can create stress for aquatic life and impair the river’s ability to support biodiversity and healthy ecosystems.

To combat these challenges, the City of Steamboat Springs, along with other partners, is actively monitoring and implementing measures to mitigate these issues in alignment with the Yampa River Health Assessment and Streamflow Management Plan. Key measures include:

1. strategic releases from Stagecoach Reservoir

2. restoration of the riparian forest along the banks to increase shading of the river

3. recreational closures of the river through town when the river doesn’t meet established streamflow and temperature thresholds

Side channels and split flows are commonly found along the Yampa River and are an important indicator of ecological health. They are calm, slower-flowing areas of water that give fish and other aquatic species a place to rest away from the higher energy water in the main channel. These secondary channels are especially important as spawning grounds and nurseries for native fish species. These river features are considered when assessing both aquatic connectivity and structural complexity of the river.

The interconnectedness between the Yampa River and its floodplain mitigates both flood events and drought conditions. When the river swells, its overflow into the floodplain acts as a natural buffer, lessening flood impacts and protecting nearby and downstream communities from erosion and property damage. This overflow also enriches the floodplain soil with nutrient-laden sediments and new seed sources, fostering a diverse plant habitat and contributing to the area’s ecological diversity. Conversely, during droughts, a connected floodplain serves as a natural water reserve. Water stored in floodplain soils slowly seeps back into the river, maintaining flow and supporting aquatic life, especially when water levels are low.

However, in stretches where the Yampa is disconnected from its floodplain, these benefits are notably absent. The lack of overflow during floods leads to more intense and damaging flood events, while during droughts, the absence of a natural water reserve exacerbates low water conditions, harming aquatic ecosystems and leading to concerns about water availability. A disconnected floodplain loses its ability to sustain diverse habitats for wildlife, impacting the river’s biodiversity. It also diminishes the floodplain’s role in filtering pollutants and stabilizing riverbanks, leading to increased environmental stress.

Hayfields and riparian areas benefit wildlife. Greater Sandhill Cranes love both riparian wetlands and irrigated hay meadows! The Yampa River (and its tributary, the Elk River) provides abundant wetlands that serve as nesting and roosting areas, and irrigated hay meadows provide food (insects, frogs, and plants) for the omnivorous cranes.
Riparian buffer zones offer a benefit to both hayfields and the river. “Riparian” refers to the area alongside a stream that is planted with native vegetation. When riparian areas exist in between hayfields and the river, they prevent erosion while also intercepting sediment, nutrients, and pesticides before they enter the river. Establishing streamside buffers is also linked to reduced property loss, less downstream flooding, and improved wildlife and pollinator habitat.

*Photo by Sally Thurston

Channel morphology is not just determined by hydrology and geology, but biology as well!

Plants and animals big and small can actually be drivers of the physical form of a stream (Castro and Thorne, 2019).

For example, riparian vegetation tends to have a stabilizing effect on channel morphology. Beaver change streams by increasing the channel complexity and amount of fine sediment deposition. Amazingly, macroinvertebrates such as caddisfly can be drivers of channel morphology because they reduce the mobility of the sediments along the riverbed. Conversely, macroinvertebrates and fish can also serve to increase bed mobility, due to the disturbance that results when fish forage for a macroinvertebrate meal!

Beaver create beneficial heterogeneity in the landscape by creating complicated waterworks that slow water flows and allow the land to store water like a sponge, a key factor to preventing wildfires. They build structures that increase habitat complexity, improve soil moisture, and enhance aquifer water storage, thus building resiliency for dry times, and mitigating the power of floods. They build healthy riparian areas that support biodiversity. In spite of all of these benefits, beaver came to be considered a nuisance when their dams conflicted with human-built infrastructure or needs. Now we know that these ecosystem engineers can help humans adapt to a warmer and drier future, if we let nature do its work.

Macroinvertebrates are amazing little creatures that support a huge food web and can tell us a lot about the water quality of a river. Historically, information on these small animals has been collected irregularly, and there are large gaps in the data set. Through the Yampa River Scorecard Project, Friends of the Yampa is working with local and state partners like Colorado River Watch to fill in the gaps and become a source of ongoing, long-term information about the benthic macroinvertebrate communities in the Yampa River.