Littlerock Dam and Reservoir

Palmdale Water District

6 Jun 201803:15

Summary

TLDRThe Little Rock Dam, constructed in 1924 and renovated in 1994, is a crucial water storage facility for the growing community of Little Rock. Engineered by John Eastwood, it was once the largest multiple arch dam, standing 124 feet high and 576 feet wide. Controversies in 1932 revolved around the spillway design, especially after the St. Francis dam failure. Sediment removal is vital for maintaining water storage capacity, crucial during droughts, but is complicated by the presence of the endangered Diorio toad in the watershed area. The dam's reservoir is replenished by natural runoff and rainfall, with water transferred to Lake Palmdale for treatment and distribution.

Takeaways

🏗️ The Little Rock dam was constructed in 1924 and was the largest multiple arch dam at that time.
👷 John Eastwood, a renowned engineer in the Western Region, was responsible for the dam's construction.
🌊 The dam's design was innovative, featuring a 124 feet high and 576 feet wide multiple arch structure, which was new to the area.
💦 The dam's primary purpose was for water storage to meet the needs of a growing community.
🚨 In 1932, controversy arose over the dam's spillway design and function, following the St. Francis dam failure.
🔄 The Little Rock dam was renovated in 1994 to increase the reservoir's storage capacity by removing sediment.
🌊 Sediment removal is crucial for maintaining water storage capacity, as accumulated dirt can limit the dam's ability to hold water.
🌧️ The dam and reservoir are replenished by natural runoff from snow packs and rainfall in the local mountains.
🐸 The Diorio toad, an endangered species, inhabits the watershed area of the dam, affecting sediment removal operations.
🛠️ Mitigation efforts are necessary due to the presence of the endangered species to safely remove accumulated sediment.
💧 Water from the Little Rock reservoir is transferred to Lake Palmdale and then treated for distribution.

Q & A

What was the primary purpose of constructing the Little Rock dam?
-The Little Rock dam was built primarily for storage to meet the growing community's storage needs.
When was the Little Rock dam constructed and what made it significant at the time?
-The Little Rock dam was constructed in 1924 and was the biggest and tallest multiple arch dam at that time.
Who was the engineer responsible for the construction of the Little Rock dam?
-John Eastwood was the engineer responsible for the construction of the dam, and he was well known in the Western Region for dam construction.
What controversy arose in 1932 regarding the Little Rock dam?
-The controversy in 1932 was mainly about the spillway design and function of the Little Rock dam, following the failure of the St. Francis dam just four years prior.
What was the role of the new state agency in the context of the Little Rock dam?
-The new state agency was overseeing dam safety, which was particularly relevant after the St. Francis dam failure and in the context of the Little Rock dam's spillway design controversy.
When was the Little Rock dam renovated and why?
-The Little Rock dam was renovated in 1994 to increase the storage capacity of the reservoir.
Why is removing sediment from the Little Rock dam important?
-Removing sediment is important because accumulated dirt behind the dam takes the place of water that could be stored, limiting the dam's ability to store water, which is crucial especially after droughts.
What impact did the Diorio toad have on the operation of the Little Rock dam?
-The Diorio toad, an endangered species found in the watershed area of the dam, had a significant impact on the ability to utilize the dam and remove sediment due to the need for mitigation measures.
How is the Little Rock dam and reservoir fed?
-The Little Rock dam and reservoir are fed by natural runoff from snow packs in the local mountains and from rainfall.
What happens to the water after it enters Lake Palmdale?
-After entering Lake Palmdale, the water is transferred to the district's water treatment plant where it is treated for distribution.
What is the significance of water storage in the context of the Little Rock dam?
-Water storage is very important, especially after experiencing droughts, as it ensures a valuable resource for the community and enhances the dam's ability to serve its purpose.

Outlines

00:00

🏗️ Little Rock Dam Construction and Controversy

This paragraph discusses the construction of the Little Rock dam in 1924, which was the largest multiple arch dam at the time. Engineer John Eastwood was responsible for its design, introducing an arch design that was new to the area. The dam's primary purpose was for water storage to meet the needs of a growing community. A significant controversy arose in 1932 regarding the spillway design and function, especially after the St. Francis dam failure and the establishment of a state agency to oversee dam safety.

🌊 Renovating and Maintaining the Little Rock Dam

The Little Rock dam was renovated in 1994 to increase its storage capacity by removing sediment that had accumulated over the years. Sediment accumulation reduces the dam's ability to store water, which is crucial for the community, especially during droughts. The removal of sediment is essential for maintaining the dam's function as a valuable water resource. However, the presence of the Diorio toad, an endangered species in the watershed area, has complicated sediment removal efforts due to the need for extensive mitigation measures.

🌿 Watershed and Water Treatment Process

The Little Rock dam and reservoir are fed by natural runoff from snow packs in the local mountains and rainfall. The water is then transferred to Lake Palmdale, where it undergoes treatment at the district's water treatment plant before being distributed. The paragraph highlights the importance of the dam and reservoir in the water supply chain, from natural sources to the final distribution for community use.

Mindmap

Keywords

💡Dam

A dam is a barrier constructed across a watercourse to hold back water and create a reservoir. In the video, the Little Rock dam is the central theme, being built in 1924 to meet the storage needs of a growing community. The dam's construction and renovation are critical to the video's narrative, highlighting its importance in water storage and community development.

💡Storage

Storage in this context refers to the capacity to hold water in a reservoir created by a dam. The script emphasizes the dam's role in storing water, which is vital for the community, especially during droughts. The renovation in 1994 was aimed at increasing the storage capacity by removing sediment, demonstrating the ongoing need for water management.

💡Multiple Arch Dam

A multiple arch dam is a type of dam design characterized by a series of arches that distribute the water pressure along the dam's length. The Little Rock dam, being the biggest and tallest of its kind at the time of construction in 1924, exemplifies this design. The script mentions the novelty of the arch design in the area, indicating its significance in dam engineering.

💡Engineer

An engineer in this script refers to a professional responsible for the design and construction of the dam. John Eastwood, mentioned in the video, was a well-known engineer in the Western Region for dam construction, emphasizing the expertise required for such projects and the role of engineers in community infrastructure.

💡Spillway

A spillway is a part of a dam that allows excess water to flow out and prevent the dam from being overtopped. The script discusses the controversy over the Little Rock dam's spillway design in 1932, following the failure of the St. Francis dam, underscoring the importance of dam safety and the evolution of engineering practices.

💡State Agency

A state agency in this context is a government body responsible for overseeing safety regulations, such as dam safety. The script mentions a new state agency that was formed after the St. Francis dam failure, highlighting the role of government in ensuring public safety and infrastructure integrity.

💡Sediment

Sediment refers to the solid particles that settle at the bottom of a liquid, such as water. In the script, sediment accumulation behind the dam is a concern because it reduces the dam's storage capacity. The process of removing sediment is important for maintaining the dam's functionality and the community's water supply.

💡Endangered Species

An endangered species is a type of organism that is at risk of extinction. The Diorio toad, found in the watershed area of the Little Rock dam, is highlighted as an endangered species that impacts the dam's operations, particularly sediment removal, due to environmental conservation concerns.

💡Watershed

A watershed is an area of land that drains all the streams and rainfall to a common outlet, such as a river or lake. The script mentions the watershed area of the Little Rock dam, which is significant because it is the source of the dam's water supply and is also the habitat of the endangered Diorio toad.

💡Runoff

Runoff is the flow of water that occurs when excess rainwater, meltwater, or other sources of water flow across the Earth's surface. The script describes how the Little Rock dam and reservoir are fed by natural runoff from snow packs and rainfall, illustrating the natural hydrological cycle that supports the dam's water storage function.

💡Water Treatment Plant

A water treatment plant is a facility that processes water to make it safe for human consumption. The script mentions that water from the Little Rock reservoir is transferred to Lake Palmdale and then treated at a water treatment plant before distribution. This highlights the final step in the process of making stored water usable for the community.

Highlights

The dam was built primarily for storage to meet the growing community's needs.

Little Rock dam, constructed in 1924, was the biggest tallest multiple arch dam at that time.

John Eastwood, a well-known engineer in the Western Region, was responsible for the dam's construction.

The arch design of the dam was new and controversial to the local area.

Controversy in 1932 was mainly due to the spillway design and function, following the St. Francis dam failure.

A new state agency was overseeing dam safety, adding to the controversy.

Little Rock dam was renovated in 1994 to increase the storage capacity of the reservoir.

Removing sediment from the dam is crucial for maintaining its water storage capacity.

Water storage is vital, especially after experiencing droughts.

The Diorio toad, an endangered species, was found in the watershed area, impacting dam utilization.

Mitigation efforts were required to remove accumulated sediment due to the presence of the endangered species.

Little Rock dam and reservoir are fed by natural runoff from snow packs and rainfall.

Water from the reservoir is transferred into Lake Palmdale for treatment and distribution.

The dam's maintenance and sediment removal are essential for the community's water supply.

The dam's history and renovation highlight the importance of water resource management.

The presence of an endangered species adds a layer of complexity to dam management.

The dam's design and function have evolved over time to meet changing needs.