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Dam Owners- Impact of Plants on Earthen Dams


Quiz Questions

1.Most dam safety engineers, including state and federal officials, consultants, and other experts involved with dam safety, disagree that when trees and woody plants are allowed to grow on earthen dams, they can hinder safety inspections, can interfere with safe operation, or can even cause dam failure.
True
False
2. What does ASDSO mean?
Association of State Dam Safety Officials
American State Dam Safety Officials
American Safety Dam State Officials
None of the above
3.Some Dam-owners believe that the more woody vegetation on a structure, the better — thus making it very difficult for state dam safety officials to request its removal.
True
False
4.Twenty-nine states indicated documented evidence where vegetation on dams has either caused __________or negatively affected their safe operation.
Dam failure
Dam safety
5.What does NPDP stand for?
National Performance of Dams Program
National Plants and Dams Program
National Performance of Dams and Plants
None of the above
6.Limited cost information for removing trees and brush or for repairing damages caused by vegetation at dams is available from the states or federal agencies.
True
False
7.Several site-specific factors can influence tree removal costs. These include size and type of trees, growth density, total job size location of growth, embankment slope steepness, slope condition, degree and type of required surface treatment, and regional labor and construction indices.
True
Use wet methods when intact removal is infeasible
8.__________ appear to be a major dam safety issue for many states.
Trees
Removal cost
9.All state and federal agency dam safety officials and experts agree that trees have no place on dams and need to be managed and controlled on both existing and new dams for at least some important reasons:
Trees and dense vegetation hinder effective dam inspections
Tree roots can cause serious structural instability or hydraulic problems, which could lead to dam failure and possible loss of life
Trees and brush attract burrowing animals, which can in turn cause serious structural or hydraulic problems
All of the above
10._________________is likely the most common misconception associated with tree growth and tree root development.
Tree Root Soil Stabilization
Dam Safety
11.What does FEMA stand for?
Federal Emergency Management Agency
Federal Emergency Management Association
Federal Excavation Management Agency
None of the above
12.Woody Vegetation Control Versus Dam Performance is an issue that is clearly understood by many dam owners, operators, inspectors, dam safety regulators, engineers, and consultants.
True
False
13.Root systems of trees and woody vegetation consist of some primary components. They are
Root ball
Lateral transport root system
a & b
None of the above
14.Soil air void content is one of the most critical factors for continual tree root development. This factor is critical since both soil density and soil oxygen content are dependent upon the amount of air voids present in a soil mass.
True
False
15.The lateral transport roots will typically be better developed on the uphill side of the tree than on the downhill side of the tree.
True
False
16.The _____________that is typically directly below the trunk of the tree provides vertical support while the lateral transport roots provide lateral support for the tree.
Root ball
Vegetation
17.One of the best methods of controlling tree and woody vegetation growth on new earthen dams and existing earthen dams where remediation requires placement of additional embankment fill soil is to compact the embankment fill soils to a high degree of compaction.
True
False
18.What does NID stand for?
National Inventory of Dams
National Independency of Dams
National Insurance for Dams
None of the above
19.Soil Moisture Uptake of many species of trees far exceeds that which most individuals would estimate as a normal requirement of water for continual tree growth and tree root development.
True
False
20.The ______________is located immediately above the phreatic surface or seepage line where embankment fill soils have become saturated as a result of capillary rise caused by capillary forces in the soil voids.
Zone of saturation
Effective particle size