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| *Most common temporary stream crossing | | *Most common temporary stream crossing |
| *Most appropriate for short-term use | | *Most appropriate for short-term use |
− | *Generally appropriate for perennial or '''intermittent streams''' | + | *Generally appropriate for perennial or <span title="a well-defined channel that contains. water for only part of the year, typically during winter and spring when the aquatic."> '''intermittent streams'''</span> |
| *Generally preferred over fords as disturbance to stream is limited to construction and removal | | *Generally preferred over fords as disturbance to stream is limited to construction and removal |
| </td> | | </td> |
Revision as of 13:07, 12 June 2019
Typical temporary stream crossing methods and their applicability.
Link to this table
Stream crossing type |
Applicability |
Limitations |
Temporary bridge |
- Results in least disturbance to stream bed and banks compared to other stream crossing methods
- Typically no time of year restrictions for use
- Generally most appropriate for streams with high flow velocities or steep gradients
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Use in large channels may require pier(s) or other supports, which increase disturbance to stream (see Construction recommendations and specifications) |
Temporary culvert (pipe) |
- Most common temporary stream crossing
- Most appropriate for short-term use
- Generally appropriate for perennial or intermittent streams
- Generally preferred over fords as disturbance to stream is limited to construction and removal
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- May not be appropriate for large streams or during high flow conditions
- Causes greatest obstruction to flow
- May damage channel cross-section; culvert crossings should be planned to limit the number of crossings needed
- Not appropriate for streams that are vertically degraded or incised
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Temporary ford (drive-through) |
- Most appropriate for short-term use
- Generally appropriate for ephemeral or low flow perennial streams
- Used when bridge or culvert crossings are not feasible; typically very shallow streams where stream banks are less than 4 feet above the stream invert
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- Use should be limited to dry season
- Use should be limited to streams whose beds are armored
- May degrade water quality due to contact with construction vehicles and equipment
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