This course will introduce you to the principles and practices of identifying problems in existing earthen dams that are the result of uncontrolled plant activity. Some common misconceptions concerning plant growth on dams will be presented. This course summarizes a comprehensive survey of plant impacts on earthen dams across the United States and outlines the steps necessary to protect a dam from potentially serious damage from the growth of trees and woody vegetation. The results of the survey indicate that there is too often a wide gap between the known best practices of plant management relative to dam safety and the perceived acceptable level of maintenance by many dam owners. This course demonstrates that some plant growth can potentially damage earthen dams beyond repair, and emphasizes the concept that delayed control and repair of plant growth usually results in increased total costs of repair. The course presents the best practices methods for controlling or removing species of plants that have been the most common causes of damage to earthen dams.

Learning Objectives

• Awareness of the characteristics and seriousness of dam safety problems associated with plant impacts on earthen dams
• A higher level of understanding of dam safety issues associated with plant impacts on earthen dams by reviewing current damage control policies
• State-of-practice guidance for remediation design considerations associated with damage associated with plant impacts on earthen dams
• Rational and state-of-practice techniques and procedures for management of desirable vegetation on earthen dams
• Useful statistics on dams damaged by plant growth
• A collective view of state and federal dam safety officials
• The different methods for repairing damage caused by plants
• The recommended methods controlling different species of plants
• How to recognize different species of plants
• The use of construction methods for control of plant growth
• The relationship between well compacted soil and plant growth
• Some rules of thumb for analysis of dam safety conditions
• The 5 safety inspection and evaluation zones
• The pros and cons of regular maintenance versus long term remediation
• The compounding affect of plant growth attracting undesirable wildlife
• The compounding physical and economic effects of delayed maintenance
• Guidelines for estimating costs of maintenance and remediation
• The critical need to maintain plant growth in a timely manner