Category Archives: Floods

Boulder Colorado Flood of September 2013

The city of Boulder, Colorado is flooded after several days of torrential rains. Here’s some useful links if you want to get up to speed on what’s going on.

Turn around, don’t drown. If you’re in the affected area, get authoritative news from local sources (and not this blog).


For raw unfiltered news of what is happening, listen to the emergency services scanner for the Boulder area. The Boulder County Sheriff and Fire feed has over 800 listeners as of this writing. You’ll want to listen through headphones, because the feed is a stereo feed with fire/rescue on one channel and police on the other.

A good text counterpart to this is the Boulder Office of Emergency Management twitter feed, which has brief and authoritative updates about the situation. The Boulder OEM web site echoes those updates in more detail.

Local news media

The Daily Camera is Boulder’s daily newspaper, and it has continuous updates on the situation. Their September 12 story is a long list of incidents, warnings, accounts and stories about what’s going on. Twitter: @dailycamera

There’s flooding in the Denver area as well, and the Denver Post is on it. A September 12 Denver Post story notes the extent of the damage:

Heavy rain and massive flooding threatens towns and cities up and down the Front Range into the day Thursday as communities were evacuated, roads closed and emergency shelters set up.
Three people were confirmed dead and at least one missing.
At an afternoon news conference Boulder officials said at least 12 dams in the county had overflowed.The Boulder airport was closed as well as Boulder mountain parks and open space until further notice.


As ever, Twitter is on the scene when there’s news. The #boulderflood and #cowx hashtags have been trending, with photos, video, and brief accounts of what’s happening. A #coflood tag covers flooding across Colorado.


A map has been removed per the owner’s request on 25 October 2013.

The City of Boulder has a road closures map with markers showing where roads are closed or impassible. Officials are recommending that people stay off the roads.

As of Thursday, September 12 in the evening I have not been able to find a good clear map that shows the full extent of affected areas, and emergency operations are still in rescue mode.

Google has a crisis map for the 2013 Boulder Floods. This is a snapshot as of Friday, September 13, in the morning. The dots mark places where roads are closed, and the evacuation area for Longmont is shown as the St Vrain River bisects the town. Look at the current map for the latest details, and know that roads are being opened and closed in response to changing needs.

Screen shot 2013-09-13 at 10.39.12 AM

Cities affected by the flood

This is an incomplete list of towns and villages beyond Boulder that are affected by the flood.

Lyons, Colorado: Photos on Facebook at the Lyons, Colorado page and at Kenneth Wajda’s site I Am Lyons Colorado.

A National Weather Service alert warns of flash flooding hazards in Lyons, Jamestown, Peaceful Valley, Allenspark, Raymond, Meeker Park and Longs Peak.

Another alert warns for flooding in the following locations: Northwestern Arvada, Western Westminster, Boulder, Western Longmont, Southwestern Broomfield, Lafayette, Louisville. Superior, Lyons, Jamestown, Salina, Eldorado Springs, Crisman. Gold Hill, Niwot, Summerville, wallstreet, Rocky Flats. Raymond, sunshine, white Ranch open space and Allenspark.

The Jefferson County Sheriff has emergency information on a Blogspot weblog.

KRDO has a log of Colorado Springs flooding information.

Water levels

The Boulder Creek hydrograph shows current water levels measured in Boulder. As of this writing the creek is in “moderate flood stage” and rising.



This flood is being compared to the 1894 Boulder flood. The Boulder History Museum account of that flood reads in part:

As rains continued, adding to spring runoff, Boulder Creek began to rise. The threat of a flood was serious. Overnight, the creek rose out of its banks and rushed through the canyons above Boulder. By daybreak the creek had turned into an angry river, carrying debris from the settlements and bridges it destroyed in the mountains. In Boulder, the creek had begun its destruction as it swept the Sixth and Twelfth Street bridges downstream. The flood submerged railroad tracks, roads and farms, and tore down telephone and telegraph poles, taking Boulder’s means of transportation and communication out of commission.


July 8, 2013 Toronto flooding

The streets of Toronto are full of water as over 100 mm of rain (about 4 inches) has fallen in some areas. Meteorologists are making comparisons with Hurricane Hazel, which flooded the area in 1954.

Some of the best brief accounts are on Twitter, using the various hashtags #TOflood, #floodTO, #TOstorm, #stormTO, and #darkTO.

I listened to CBC Radio 1 Toronto for a while to get a sense for how bad it is. CFTR, 680 News, is an all-news radio channel, here linked via TuneIn. There are more photos at the Globe and Mail, and at the moment there's live TV coverage online on CP24.

Lots of people are without power; there's a power outage map from Toronto Hydro but it appears to be incomplete; the @torontohydro Twitter feed says 300,000 without power as of about 9:00 p.m. ET.

June 27, 2013 flooding in Ann Arbor

Several streets in Ann Arbor have flooded as a result of slow-moving storm cells that passed through the city on the afternoon of Thursday, June 27, 2013. Reports are still filtering in, but here’s what I know about right now.

The City of Ann Arbor is building a “Citizen Storm Corps” volunteer group to assist in stormwater/flooding data collection. Volunteers will visit Large Event Data Gathering locations after significant rain events, record visual observations about the stormwater’s behavior at that location using a LEDG Stormwater/Flooding Reporting Form, and submit the data to the city. If interested in volunteering, e-mail

US-23 at Warren Road

From the National Weather Service, all caps in original.


Depot Street.

Depot between North Main and Fourth has flooded. This is an ambulance route, and at least one ambulance had to turn back because of the high water.


State Street.

South State Street near Yost Arena has flooded. U of Michigan athletes were out pushing stalled cars.

Huron and Washington near the Ann Arbor Railroad

South Fifth near Fingerle Lumber

Behold Lake Fingerle

Hatcher Library basement

The basement of the University of Michigan Hatcher Graduate Library took on some water; a truck from Belfor was there later in the evening.

Hill and South Division

Detroit Street at Beakes>

South Industrial

Just south of Kroger

Hoover and Mary

N. Ashley and Felch

A 55mb .MOV file showing the flooding at that corner; it plays on Macs with Quicktime. From @voxphoto, via the Ann Arbor Chronicle.

South Main between Packard and Madison

Looks like this was taken from inside Hook Logic.

More local coverage:

Related articles – collaborative analysis of storm impact
March 28, 2013 North Quad flood

June 2013 Calgary, Alberta floods (#yycflood, #abflood)

Flooding of the Bow and Elbow Rivers inundated downtown Calgary, Alberta on June 21, 2013. Flooding and flash flooding has affected large parts of southern Alberta, due in part to a slow-moving storm front that is dumping a lot of rain on the area, up to 7.5 inches in 2.5 days. Three people have died from the flooding.

If you’re in Calgary, Alberta reading this, you should know that it’s likely to be out of date and incomplete. Check with local authorities and local news services for the most current information.

News reports: be patient, prepare for power outages, limit travel, and conserve water.

The below video is published on Youtube by the Calgary Police, showing about 60 minutes of helicopter footage of the flooding.

Map from Google Crisis Response, snapshot on June 21, 2013.


News sources:

Social media:


Official sources:


Related articles

Calgary flood: Alberta residents describe what they’re seeing –
Alberta floods force thousands from homes
Map/Video: 100,000 to be evacuated from Calgary floods; downtown emptied
Lockdown of Calgary police makes Twitter a massive #fail in emergency communications
LIVE: Flood waters lay siege to Calgary and southern Alberta
#yycflood: Scaffolding section gives way on new bridge under construction at the Bow River

Wet West Michigan: maps of flooding, April 2013

This map from MLive shows roads closed due to flooding in Western Michigan. (Turn around, don't drown). Click through for the interactive version.

Screen shot 2013-04-21 at 3.23.18 PM
A similar map from NOAA shows flood gauge readings across the area.

Screen shot 2013-04-21 at 3.26.59 PM
The purple gauge in this above map is Grand Rapids at Comstock Park, which is showing flooding at almost 6 feet above flood stage.

Screen shot 2013-04-21 at 3.29.56 PM
The historical big flood in Grand Rapids is from 1904; this collection rephotographs scenes from that flood in 2004.

March 28, 2013 North Quad flood

North Quad at the U of Michigan had a flood today, causing classes to be cancelled and students to be evacuated from their rooms. There is no estimate of the damage at this time, but it’s extensive.

The University of Michigan School of Information has a flood information page with reschedule and relocate information for classes and talks.

All media inquires about the flooding should be directed to Kelly Cunningham in the UM Public Affairs Office:, 734-936-5190.


Photo by Heidi Skrzypek, UMSI staff

From the Michigan Daily “Flooding forces cancellation of classes in North Quad“:

According to Ken Campbell, North Quad’s maintenance mechanic, a broken joint pipe on the building’s fire suppression system was responsible for the flooding. The break occurred in the East Stairwell on the fourth floor of the building, he said. When the pipe lost pressure, the system automatically turned the water pump on to add pressure, exacerbating the flow from the three-inch pipe.

Campbell estimated that “thousands and thousands” of gallons poured from the pipe before it was turned off 20 minutes later.

From the Nearly 100 students displaced by flooding at University of Michigan’s North Quad

Jeff MacKie-Mason, dean of the U-M School of Information, sent an email to the school community stating that the The Ehrlicher Room in North Quad sustained major damage in the flooding.

“We will not be able to use it for some time, perhaps several months (the ceilings may need to be replaced, walls may need repair, the carpet and our extensive electronics equipment may need replacement),” MacKie-Mason wrote in the email.

From the Ann Arbor Chronicle: nothing.

From the Ann Arbor Journal: nothing.

2 of of 4 isn’t bad.


Related articles

North Quad Community Open House, Thursday March 31, 2011, 3p-6p
And This is Why Ann Arbor Is Obsessed With Itself
Living With Floods: How you can minimize the damage

Hurricane Isaac flood maps and flooding predictions

Hurricane Isaac brought with it high winds and a substantial amount of rain, and both of those combined has led to a lot of flooding. Here are some maps I've collected while the storm is still underway. You should know that for each of them I'll also give a link to the underlying mapping source so that you can get current information.

If you are in the affected area and need details about flooded roads or the risk of dams or levees bursting or anything else, do not trust this weblog for current information; seek out official and up to date sources.

Most of the maps are dated August 30, 2012, unless otherwise noted.


A good source for maps of observed precipitation is, specifically the AHPS (Advanced Hydrometeorological Prediction Service). Here's a 7 day observed rainfall for Louisiana from that service, showing some areas with upwards of 20 inches of observed rainfall.

Predicted rainfall

A good source for rainfall predictions running out to the next 5 days (120 hours) is the Quantitative Precipitation Forecast (QPF). These models are updated several times a day and give rainfall estimates over the entire country. (Your rainfall will differ.) This is the run from Thursday, August 30, 2012, showing a predicted 5 day course for the remnants of Isaac to dump rain up the Mississippi and Ohio River valleys.

P120i00Predicted flooding

The National Weather Serivce Watch, Warning, Advisory Display shows this map with areas in pale green with warnings of potential floods, darker green (Arkansas) with current flood conditions, and parts of Louisiana and Mississippi with flash flood warnings. The accompanying text for some forecasts note that because of the dry and drought conditions the ground will be hard, and thus less able to absorb moisture leading to heavy runoff and flooding.

Picture 13

River gauges, current

Many rivers have flood gauges which measure and report current flood status. This is a map from's River Observations page showing the whole nation, with flooding marked in color. You can zoom in to individual observations as well.

Here's a zoom of the New Orleans area for the same data. Please note that the gauges are only on rivers, and will not show flash flood areas, levee breaches, or other places where water is not usually found.

Picture 11
Satellite imagery

I'll be on the lookout for satellite photos that show flooding; those usually don't appear until after the storm has cleared, because any imagery sensitive to water will pick up the clouds first.  Here's a NASA Aqua/MODIS image, pulled from their Rapid Response Imagery datasets.

Picture 12