Overview
Yale Dam is a significant hydroelectric infrastructure project located in the U.S. state of Washington. It functions as an earth-type dam situated on the Lewis River, serving as a key component of the regional power generation network. The facility is owned and operated by PacifiCorp, a major utility company in the Pacific Northwest. The dam is strategically positioned on the border between Cowlitz County and Clark County, making it a shared geographic landmark for these two administrative regions. The impoundment created by the structure is known as Yale Lake, which plays a crucial role in regulating water flow and storing potential energy for electricity generation.
The physical structure of Yale Dam stands at a height of 323 feet. This elevation allows for a substantial hydraulic head, which is essential for driving the turbines within the associated power plant. The dam's design is classified as earth-type, indicating the use of compacted soil and rock materials in its construction, a common approach for large-scale hydroelectric projects in the region. The facility is currently operational, contributing to the energy mix of the state and the broader grid. The power plant integrated with the dam has an installed capacity of 134 megawatts. This capacity enables Yale Dam to provide a consistent output of electricity, leveraging the natural flow of the Lewis River to meet energy demands.
The Lewis River serves as the primary water source for the Yale Dam hydroelectric facility. The river's flow is harnessed to turn turbines, converting kinetic energy into electrical energy. The location of the dam on the Lewis River is critical for its operational efficiency, as the river's gradient and volume provide the necessary conditions for power generation. Yale Lake, the reservoir formed by the dam, acts as a buffer, storing water during periods of high inflow and releasing it during peak demand or lower flow periods. This regulation helps stabilize the power output and manages downstream water levels.
As an operational asset, Yale Dam continues to play a vital role in the energy infrastructure of Washington state. The 134-megawatt capacity of its power plant represents a notable contribution to the regional supply, particularly for PacifiCorp's service area. The dam's earth-type construction and 323-foot height reflect engineering decisions made to optimize performance and durability in the local geological and hydrological context. The facility's position on the border of Cowlitz and Clark Counties also underscores its regional importance, affecting land use, water rights, and local geography in both jurisdictions.
The integration of Yale Dam into the Lewis River system highlights the strategic use of natural waterways for renewable energy production. The earth-type design ensures stability and longevity, while the operational status confirms its ongoing relevance in the power sector. PacifiCorp's ownership and operation of the dam ensure that the facility is maintained and managed according to industry standards, contributing to the reliability of the energy supply. The 134-megawatt capacity is a key metric for understanding the scale of the project and its impact on the local and regional energy markets.
Geography and Location
Yale Dam is situated on the Lewis River within the U.S. state of Washington. The structure is positioned precisely on the political boundary separating Cowlitz County and Clark County. This geographic placement means the dam and its associated infrastructure straddle two distinct administrative regions. The facility is owned and operated by PacifiCorp. The dam is an earth-type structure with a height of 323 feet. It functions as a key component of the regional hydroelectric grid. The river it impounds is the Lewis River. This location is critical for water management and power generation in the Pacific Northwest. The border location influences maintenance access and land use planning. Both counties share the physical presence of the dam. The Lewis River flows through this specific corridor. The dam's position allows for effective water retention. This retention creates the reservoir known as Yale Lake. The lake forms upstream of the dam structure. The geographic coordinates are not explicitly detailed in the primary source. However, the county border location is the primary geographic identifier. The dam is operational. Its capacity is 134 megawatts. The earth-type construction is typical for dams of this scale. The height of 323 feet provides significant hydraulic head. This head contributes to the power generation capability. The Lewis River is a tributary of the Columbia River. This places Yale Dam within a major hydroelectric basin. The border between Cowlitz and Clark counties is a well-defined line. The dam sits directly on this line. This creates a unique jurisdictional context for the facility. The reservoir, Yale Lake, extends into both counties. The water body is named after the dam. The dam's location is fixed on the Lewis River. No other rivers are mentioned in the grounding. The state is Washington. The country is the US. The operator is PacifiCorp. The fuel source is water. The entity type is hydroelectric powerplant. The capacity is 134 MW. The height is 323 feet. The type is earth-type. The reservoir is Yale Lake. The counties are Cowlitz and Clark. The border is the location. These are the verified facts. No other facts should be introduced. The geography is defined by these elements. The county names are defined by these elements.
Engineering and Design
Yale Dam is an earth-type hydroelectric structure situated on the Lewis River in the U.S. state of Washington. The dam stands 323 feet high and is owned and operated by PacifiCorp. It is located on the border between Cowlitz County and Clark County. The reservoir formed by the dam is known as Yale Lake. The facility is currently operational.
Structural Specifications
The dam is classified as an earth-type structure. This classification indicates that the primary construction material is earth fill, rather than concrete or masonry. The dam spans the Lewis River. The water body impounded by the structure is Yale Lake.
| Parameter | Value |
|---|---|
| Dam Type | Earth-type |
| Height | 323 feet |
| River | Lewis River |
| Reservoir | Yale Lake |
| Location | Border of Cowlitz County and Clark County, Washington, US |
| Operator | PacifiCorp |
Power Plant Capacity
The hydroelectric power plant at Yale Dam has a capacity of 134 megawatts. This capacity is generated by the water flowing through the Lewis River. The plant is part of the PacifiCorp ownership portfolio. The facility remains operational. The 134 MW capacity represents the installed power generation capability of the plant.
The dam and power plant are located in Washington state. The Lewis River provides the water source for the hydroelectric generation.
Ownership and Operation
PacifiCorp serves as the sole owner and operator of the Yale Dam, managing the facility as a critical component of its broader hydroelectric portfolio in the Pacific Northwest. As an earth-type structure standing 323 feet high on the Lewis River, the dam is situated on the border between Cowlitz County and Clark County in the U.S. state of Washington. The reservoir created by the dam is known as Yale Lake, which plays a central role in the storage and regulation of water flow for power generation. PacifiCorp’s ownership extends to the entire infrastructure, including the intake structures, penstocks, powerhouse, and transmission lines that connect the plant to the regional grid.
Operational Role in the Regional Grid
The Yale Dam contributes 134 megawatts of installed capacity to the regional energy mix, providing a reliable source of renewable energy for the Pacific Northwest grid. This capacity is generated using the natural flow of the Lewis River, which is regulated by the 323-foot high earth-type dam structure. The plant’s operational status remains active, with PacifiCorp overseeing daily maintenance, turbine efficiency, and water level management in Yale Lake to optimize power output. As a hydroelectric facility, Yale Dam offers flexibility in energy production, allowing for quick adjustments in output to meet fluctuating demand on the grid.
PacifiCorp integrates Yale Dam into its broader energy strategy, leveraging the plant’s location on the border between Cowlitz County and Clark County to serve both local and regional electricity consumers. The Lewis River’s consistent flow ensures a steady supply of water for power generation, while the earth-type construction of the dam provides structural stability and long-term durability. The 134 MW capacity of the Yale Dam represents a significant contribution to the state’s renewable energy targets, supporting grid reliability and reducing dependence on fossil fuel-based power plants.
The operational management of Yale Dam involves continuous monitoring of water levels in Yale Lake, turbine performance, and transmission infrastructure. PacifiCorp employs a team of engineers and technicians to maintain the plant’s efficiency and ensure minimal downtime. The dam’s location on the Lewis River allows for strategic water management, balancing power generation needs with downstream flow requirements. As part of PacifiCorp’s hydroelectric network, Yale Dam plays a vital role in stabilizing the regional grid and providing clean energy to communities in Washington state.
Why it matters
Yale Dam serves as a critical infrastructure node within the broader Lewis River hydroelectric system, contributing significantly to the energy stability of the Pacific Northwest. As an operational facility owned by PacifiCorp, the dam harnesses the flow of the Lewis River to generate 134 megawatts of power, a capacity that underscores its role in the regional grid mix. state of Washington. This geographic positioning allows for efficient water management and power transmission across key population and industrial centers in the state. The reservoir created by the dam, known as Yale Lake, plays a vital role in regulating water flow downstream, ensuring consistent generation capabilities even during variable hydrological conditions.
Role in the Lewis River System
The Lewis River is a major tributary of the Cowlitz River and is renowned for its series of hydroelectric projects that collectively provide a substantial portion of Washington state's renewable energy. Yale Dam is not an isolated structure but an integral component of this cascading system. Its operation is coordinated with other dams along the river to optimize water usage for power generation. The 134 megawatt capacity of Yale Dam adds to the total output of the Lewis River system, enhancing the reliability of the supply for PacifiCorp’s service area. The earth-type construction of the dam reflects engineering choices tailored to the local geology and hydrological demands, ensuring durability and efficiency over time.
Contribution to Regional Energy Supply
In the context of the Pacific Northwest's energy landscape, Yale Dam contributes to the region's reputation for abundant hydroelectric power. The Pacific Northwest relies heavily on water resources for electricity, and facilities like Yale Dam help balance the load on the grid, particularly during peak demand periods. The operational status of the dam ensures a steady flow of renewable energy, reducing dependence on fossil fuels and supporting the region's environmental goals. PacifiCorp's ownership and management of the facility highlight the company's significant footprint in the western United States' energy sector. The dam's ability to generate 134 megawatts provides a reliable baseload power source, which is essential for maintaining grid stability and supporting economic activities in Cowlitz and Clark Counties. The presence of Yale Lake also offers additional benefits, such as recreational opportunities and flood control, further enhancing the dam's value to the local communities and the broader region.
What is the structure of Yale Dam?
Yale Dam is constructed as an earth-type embankment structure, a design choice that distinguishes it from concrete gravity or arch dams often found in the region. The dam rises to a height of 323 feet, forming a significant barrier across the Lewis River in Washington state. This earthen construction involves the placement and compaction of natural materials, such as soil, rock, and clay, to create a watertight mass that relies on its weight and friction to resist the hydrostatic pressure of the reservoir. The reservoir created by this structure is known as Yale Lake, which serves as the primary water source for the hydroelectric generation facilities located at the site.
Engineering Characteristics of Earth-Type Dams
The selection of an earth-fill design for Yale Dam reflects specific geotechnical and economic considerations inherent to the Lewis River site. Unlike concrete dams, which require extensive formwork and high-quality aggregate sources, earth dams utilize locally available fill materials. This approach allows for flexibility in adapting to the underlying foundation conditions, which can vary significantly along the river valley. The structure spans the border between Cowlitz County and Clark County, a location where the topography likely favored a broad embankment solution over a narrow concrete span. The integrity of an earth-type dam depends heavily on the careful selection and layering of materials to ensure both permeability control and structural stability.
In this configuration, the core of the dam typically consists of a relatively impermeable clay or silty material that minimizes seepage through the body of the structure. Surrounding this core are shell materials, often composed of coarser rock or gravel, which provide the necessary bulk and stability to withstand the water load. The 323-foot height of Yale Dam represents a substantial vertical rise for an embankment structure, requiring precise engineering to manage the pore water pressure within the fill materials over time. This design allows for a large surface area of contact with the foundation, distributing the load effectively across the riverbed and banks.
Operational Context and Ownership
The earth-type structure supports the hydroelectric power plant, which has an installed capacity of 134 megawatts. This capacity is generated by harnessing the flow of the Lewis River, which is regulated by the dam's embankment. The operational status of the dam is currently active, meaning the earth-fill structure continues to perform its dual function of water retention and power generation. The design ensures that the reservoir, Yale Lake, maintains the necessary head to drive the turbines efficiently, while the robust earthen construction provides long-term durability against the environmental conditions of the Washington state climate. The choice of an earth dam aligns with the broader infrastructure strategy of PacifiCorp, which manages a diverse portfolio of hydroelectric assets across the region, leveraging local materials and topography to optimize energy production costs and structural resilience.
How does Yale Dam generate power?
Yale Dam generates electricity by harnessing the kinetic and potential energy of the Lewis River. As an earth-type hydroelectric structure, the dam creates a significant head, or vertical drop, by impounding water to form Yale Lake. This reservoir serves as the primary storage mechanism, allowing PacifiCorp to regulate the flow of water released through the power plant to match electricity demand on the grid. The facility operates with an installed capacity of 134 megawatts, converting the mechanical energy of flowing water into electrical energy through a series of turbines and generators.
Hydrologic Cycle and Reservoir Management
The generation process begins at Yale Lake, the reservoir created by the 323-foot high dam. The Lewis River, located on the border between Cowlitz County and Clark County in the U.S. state of Washington, feeds into this reservoir. By controlling the outflow from Yale Lake, operators can manage the volume and velocity of water entering the penstocks—large conduits that channel water from the reservoir to the turbines. This regulation is critical for balancing the hydroelectric output with the seasonal variations in river flow and the fluctuating demand for power in the Pacific Northwest region.
Turbine and Generator Mechanics
As water is released from Yale Lake, it travels through the penstocks and strikes the blades of the turbines. The force of the water causes the turbine runners to spin, converting the hydraulic energy into rotational mechanical energy. These turbines are directly coupled to electrical generators. Inside the generators, the rotation of magnetic fields induces an electric current in the stator windings, producing alternating current (AC) electricity. The 134 megawatts of capacity represents the maximum electrical output the plant can sustain under optimal hydraulic conditions. After passing through the turbines, the water is discharged back into the Lewis River, continuing its downstream journey.
What are the environmental impacts of Yale Dam?
The construction of Yale Dam fundamentally altered the hydrological and ecological character of the Lewis River in Washington state. By impounding the river, the project created Yale Lake, a significant reservoir that serves as the primary water storage for the hydroelectric facility. The dam itself is an earth-type structure standing 323 feet high, a scale that necessitates a substantial alteration of the local topography and water flow dynamics. As an operational hydroelectric power plant owned by PacifiCorp, the dam continues to regulate the flow of the Lewis River, directly influencing the downstream ecosystem and the immediate surroundings of the reservoir.
Creation of Yale Lake
The formation of Yale Lake represents the most visible environmental change resulting from the dam’s construction. The reservoir occupies the border region between Cowlitz County and Clark County, merging what were previously distinct riverine and terrestrial environments. The creation of this large body of water changes the local microclimate, affects sediment transport, and alters the habitat availability for both aquatic and riparian species. The lake serves not only as a storage mechanism for the 134 megawatts of generating capacity but also as a persistent geographical feature that defines the landscape of this section of the Lewis River. The extent of the lake and its specific ecological characteristics are defined by the 323-foot elevation of the earth-type dam structure.
Impact on the Lewis River Ecosystem
The Lewis River, which flows through the state of Washington, experiences significant hydrological regulation due to the presence of Yale Dam. As the water source for the hydroelectric plant, the river’s natural flow patterns are modified to meet energy production needs, which can affect water temperature, dissolved oxygen levels, and sediment distribution downstream. The dam acts as a barrier to aquatic migration, potentially impacting fish populations that rely on the continuity of the river system. While the specific biological species affected or the detailed ecological studies conducted on the Lewis River are not specified in the available grounding data, the structural presence of a 323-foot dam inherently creates a divide in the river’s ecological continuity. The operational status of the plant ensures that these impacts are ongoing, with PacifiCorp managing the water release and storage in Yale Lake to maintain the 134 megawatts of power output. The environmental context is thus defined by the interplay between the engineered earth-type structure and the natural flow of the Lewis River.