About Flooded Bridges
Flooded Bridges shows, at a glance, whether low roads, bridges, and causeways near a river or bay are likely to be flooded right now, whether the water is rising or falling, and when it could flood or clear.
Flooded Bridges was inspired by the frequent flooding of low-lying roads along the Millstone River in New Jersey. Locals always want to know whether the causeways are open or flooded before they head out, so they don’t have to turn around and find another route at the last minute.
What you see
You can create a personal list of monitoring locations made up of river, stream, or tidal gages. We use the spelling “gage” instead of “gauge” to match the spelling used by USGS. For each monitoring location, the site shows:
- A status for the area around the monitoring location (see below).
- The current water level, and whether it’s rising, falling, or steady.
- A 7-day chart of the water level, with the official flood levels drawn as dashed lines.
- A map of where the monitoring location can be found.
- A predicted time, when there is one, for when the area could flood or clear.
Where it covers
Flooded Bridges started with the Millstone River in NJ and now can follow flood monitoring locations anywhere in the country.
What the statuses mean
Statuses are based on each monitoring location’s action threshold, a flood level set by the National Weather Service. It’s the height where the water starts to cause problems nearby, and often when low roads begin to flood. Where the National Weather Service publishes no action threshold for a monitoring location, its minor flood level is used instead.
- CLEAR
- The water is below the action threshold.
- FLOODING SOON
- The water is rising and is expected to reach the action threshold within the next few hours.
- FLOODING
- The water is at or above the action threshold.
- CLEAR SOON
- The water is falling and is expected to drop below the action threshold within the next few hours.
These are our own estimates based on the water level. They are not official closures. A road may be closed or open regardless of what this website displays.
Predicted times
When the water level approaches the action threshold, our logic estimates when the area might flood. These predictions are experimental and actual results may vary widely with changing conditions.
Choosing your locations
Tap + Add or remove on the Status page. Search by ZIP code, city or town, or use your current location, to follow any USGS water level gages. Monitoring locations without an action or minor flood threshold can be added too, but they show only the water level, with no flood status. You can save up to 5, and your list is kept in your own browser. We do not keep track of your selections at this time.
Where the data comes from
- Water levels: U.S. Geological Survey (USGS) stream gages, which measure every 15 minutes. For tidal gages, the National Weather Service (NWS).
- Flood levels: the National Weather Service (NWS).
- Forecasts: where the National Weather Service publishes an official river or tide forecast, it’s shown on the chart and summarized under the status.
Most gages send their readings to USGS in batches, so the newest reading could be 30 to 60 minutes old.
River gages and tidal gages
River gages measure rivers, streams, and brooks. Their water rises after rain or snowmelt upstream and falls again over hours or days, so the trend is a good guide to what happens next. For these gages, Flooded Bridges shows predicted times and uses them for the FLOODING SOON and CLEAR SOON statuses. These statuses also appear when the water is very close to the action threshold and moving toward it, even without a predicted time.
Tidal gages measure bays, harbors, and tidal rivers along the coast. Their water rises and falls with the tide about twice a day, and coastal flooding usually comes from a high tide pushed higher by wind or a storm. Because every rising tide would look like it is headed for flooding, Flooded Bridges does not show predicted times for tidal gages. Their FLOODING SOON and CLEAR SOON statuses are based on how close the water is to the flood level and which way it is moving. Tidal gages are marked Tidal gage in search results and next to the location number, and their readings come from the National Weather Service, measured on the same scale as their flood levels.
Information only. Always obey posted road closures, barricades, and emergency officials. Never drive or walk through flood water. See the Terms of Use.
Contact
Questions or suggestions: [email protected]
Version –