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<td>Temporary ford (drive-through)</td>
 
<td>Temporary ford (drive-through)</td>
 
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*Most appropriate for short-term use.
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*Most appropriate for short-term use
 
*Generally appropriate for ephemeral or low flow perennial streams.
 
*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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*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
 
</td>
 
</td>
 
<td>
 
<td>
*Use should be limited to dry season.
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*Use should be limited to dry season
*Use should be limited to streams whose beds are armored.
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*Use should be limited to streams whose beds are armored
 
*May degrade water quality due to contact with construction vehicles and equipment
 
*May degrade water quality due to contact with construction vehicles and equipment
 
</td>
 
</td>

Revision as of 12:47, 19 April 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
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
  • 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
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
  • 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