Erosion Control Structure: One Rock Dam

Summary

In this instructional video, Aaron Kaufman, founder of Southwest Urban Hydrology, guides viewers through constructing three soil conservation structures: a one rock dam, a rock rundown, and a medea luna. Focusing on the one rock dam, he explains the step-by-step process to slow water velocity in low-energy systems. Key steps include digging a trench, building a splash pad, and using native seeds to promote vegetation growth. The method emphasizes creating a concave shape to enhance water retention and sediment drop-off, ultimately aiming to restore and improve land health.

Takeaways

• 🏞️ The video focuses on three erosion control structures: a rock dam, a rock rundown, and a medea luna.
• 🪨 A one rock dam is designed to slow down water velocity in low-grade channels using a single layer of rock.
• 🔨 The first step in building a one rock dam involves digging a trench and constructing a splash pad.
• 📏 When placing stones, ensure the flattest part contacts the ground to prevent tipping and maintain stability.
• 🌱 After building the splash pad, native seeds can be added above it, using stones as mulch for germination.
• ⬆️ The dam should maintain a concave shape to direct water flow through the center and prevent overflow.
• 📦 Avoid stacking rocks to maintain the single-layer height characteristic of a one rock dam.
• 🌧️ During storms, water will wash sediment into the structure, aiding in soil conservation.
• 🌿 Embedded stones help improve soil moisture, promoting the growth of seeded plants.
• 🧱 Filling gaps between stones with gravel can enhance the dam's structural integrity and effectiveness.

Q & A

What is the main focus of Aaron Kaufman's presentation?

The presentation focuses on three structures for soil conservation: a one rock dam, a rock rundown, and a medea luna.

What is a one rock dam, and what purpose does it serve?

A one rock dam is an erosion control structure built using a single layer of rock in a low-grade channel to slow down the velocity of water.

What are the initial steps in constructing a one rock dam?

The first step is to dig a trench and build a splash pad, ensuring that the flattest part of the stone is in contact with the ground.

Why is it important to maintain a concave shape in the one rock dam?

A concave shape helps to center the majority of the water flow through the structure, preventing water from flowing around it.

What materials are used for seeding above the splash pad?

Native seeds, such as alkali sacotone and wildflowers, are used, with stones serving as mulch to help the seeds germinate.

How should the stones be arranged during construction?

The stones should be fitted together tightly without stacking, maintaining a consistent elevation across the structure.

What should be done if there are gaps between the stones?

Small gaps can be filled with gravel to armor the structure and improve its effectiveness.

What additional benefits do the rocks provide once the dam is constructed?

The rocks help to improve soil moisture and support the germination of seeds by maintaining mulch.

How does the construction of a one rock dam affect sediment?

As water passes through the dam, it slows down and drops sediment, which can help restore the area.

What is the overall goal of implementing these structures?

The goal is to restore sections of property or land by conserving soil and managing water flow effectively.