River Stages
San Bernard River at Sweeny
|
River Stage Benchmarks |
|
Action
Minor Flood
Moderate Flood
Major Flood
Flood Record |
12 ft
16 ft
17 ft
18 ft
* 27 ft |
October 17-22, 1998, when 22" of rain fell in two
days
| Impacts
(as stated by NOAA) |
| 25.0 |
At levels near 25 feet water is
over the top of the dock at the Phillips Terminal near Sweeny with all
vessel traffic stopped. Widespread inundation of the left flood plain
occurs.
|
| 17.0 |
At levels near 17 feet water is
over the mid level walkway at the Phillips Terminal near Sweeny. Tractors
can not push barges upstream and are unable to dock. Water begins spilling
into the left flood plain.
|
| 16.0 |
At levels near 16 feet water is
over the mid level walkway and tugs can not push barges upstream and are
unable to dock.
|
| 14.0 |
Water is over the lowest
platform at the Phillips Terminal near Sweeny. Shipping barges moving up the
San Bernard River must fight the current and docking maneuvers are affected.
|
| 13.0 |
Water start spilling over the
right bank and covers the lowest platform at the dock just upstream from the
gage.
|
| 12.0 |
Caution stage, a strong north
wind can cause barges scrape bottom.
|
Characteristics to help determine the
following NOAA river stages.
| Bankfull
|
- Water flows out of it's normal banks.
- Can happen several times a year.
- May be a minor nuisance to people in the area.
- May flood pastures but not usually cultivated fields.
|
| Action
Stage* |
- Stage at which some person or agency needs to pay
attention to the hydrologic situation and perform a function.
- There can be no flooding at this stage.
- Action stages are not mentioned in issued products.
- Forecasts for action stages are given directly to the
action agency.
* Note: Action Stage is not be used by all Regions
|
| Flood Stage |
- The term Minor Flooding is used to indicate
minimal or no property damage. However, some public inconvenience is
possible.
- The term Moderate Flooding is used to
indicate the inundation of secondary roads. Transfer to higher elevation
may be necessary to save property. Some evacuation may be required.
- The term Major Flooding is used to
indicate extensive inundation and property damage, usually characterized
by the evacuation of people and livestock, and the closure of both
primary and secondary roads.
|
Resources:
http://www.nws.noaa.gov/om/hod/SHManual/SHMan045_FPfs.htm
http://www.srh.noaa.gov/cgi-bin/ahps.cgi?hgx&swyt2
http://www.srh.noaa.gov/wgrfc/basinlist.php?funct=ref&basin=SANB