Hurricane Harvey Drops Enough Rain On Houston To Fill 560 Dallas Cowboy Stadiums

Hurricane Harvey has wreaked havoc on certain parts of Texas over the past few days.  Winds up to 125 miles per hour have ripped through the south east coast of Texas.  Reports have started to surface Sunday with average rain fall in Houston of around 40 inches of rain.  One such report is from the Associated Press shown below:

Average rainfall totals will end up around 40 inches (1 meter) for Houston, weather service meteorologist Patrick Burke said.

Furthermore, reports over the weekend have predicted that in certain parts could reach up to 50 inches of rain.  Along with the torrential rain and wind come damage which will take years to repair.  Here is another excerpt describing the extent of the damage:

The director of the Federal Emergency Management Agency, Brock Long, predicted that the aftermath of the storm would require FEMA’s involvement for years.

“This disaster’s going to be a landmark event,” Long said.

Rescuers had to give top priority to life-and-death situations, leaving many affected families to fend for themselves. And several hospitals in the Houston area were evacuated due to the rising waters.

Tom Bartlett and Steven Craig pulled a rowboat on a rope through chest-deep water for a mile to rescue Bartlett’s mother from her home in west Houston. It took them 45 minutes to reach the house. Inside, the water was halfway up the walls.

Marie Bartlett, 88, waited in her bedroom upstairs.

“When I was younger, I used to wish I had a daughter, but I have the best son in the world,” she said. “In my 40 years here, I’ve never seen the water this high.”

It was not clear how many people were plucked from the floodwaters. Up to 1,200 people had to be rescued in Galveston County alone, said Mark Henry, the county judge, the county’s top administrative post.

Houston’s George R. Brown Convention Center was quickly opened as a shelter. It was also used as a shelter for Katrina refugees in 2005.

Here are a few pictures to convey the description in the excerpt above:

In order to understand the extent of the disaster, an exercise in dimensional analysis might shed more light on the seriousness of the storm that has caused irreparable (in some cases) damage to parts of Texas.  As stated in the article, Hurricane Harvey has dropped an enormous amount of rain -- enough to fill 560 Dallas Cowboy Stadiums.



Below, I show how to carry out the brief analysis of converting inches of rainfall into the number of stadiums which could be filled.

How Big Is The Dallas Cowboy Stadium?

How do viewers and readers understand the amount of rain that has been dropped over the weekend on the Houston area by Hurricane Harvey?  In order to comprehend the magnitude of the rainfall, a metric is needed.  A metric is a physical object with dimensions which can be used to compare an unknown quantity.  The current example is the total amount of rainfall (unknown quantity - volume).  Carrying out the analysis will shed light into this disaster that has left so many homeless along with the incomprehensible loss of life which is the result of Hurricane Harvey.


To start the brief analysis of rainfall that hit the Houston area over the weekend, the area in square miles needs to be known.  Of course, the following steps will be carried out to arrive at a final answer of the number of Dallas Cowboys Stadiums which could be filled with the total quantity of rainfall:



1) Determine the volume of the Dallas Cowboys Stadium


2) Determine the area of Houston


3) Convert from units of square miles to square feet


4) Determine the height of rainfall on Houston


5) Convert dimension of rainfall from units of inches to feet


6) Calculate total volume of rainfall


7) Calculate the number of stadiums which would be filed by rainfall



In order to understand the volume of rainfall that has fallen of Hurricane Harvey, a metric needs to be used to cast the volume of rainfall into perspective.  I have stated already that the metric which will be used is the Dallas Cowboys Stadium shown below:

Source: InternationalBowl.com

With a visual of a cross-section of the Dallas Cowboys Stadium shown below:

Source: ArchDaily

In a previous post, the volume of the Dallas Cowboys Stadium was used as a metric and therefore known to be 104 million cubic feet (interior space).  Given that volume expressed in cubic feet, all numbers which will be used to compare quantities will need to be expressed in similar units of cubic feet.  Below, all dimensions of volume -- area and height -- will be expressed in units of feet.



The second step is to determine the total area of the city of Houston which can be accomplished by a search in Google.  Enter the following query: Houston in square miles?  The following result is shown below:

With the area of Houston known, the next step is to convert from units of square miles to square feet.  Remember, in order to determine the volume, each dimension of the quantity of volume -- in this case -- area and height -- need to be expressed in units of feet.  Therefore in order to convert from units of square miles to square feet, a conversion factor needs to be obtained.



To find the unit conversion factor, the following statement is typed into Google:  How many square feet are in a square mile? The result is shown below:

Now that the unit conversion factor is known, the mathematical conversion is straightforward and shown below:

The quantity above is the area of Houston expressed in units of square feet.  In order to obtain a total volume, two parameters need to be known -- area and height.  Above, the area of Houston is 17.5 billion square feet.  According to the news excerpt above, the average rainfall was 40 inches across Houston.  For the purpose of simplicity, the average rainfall will be used across the entire 627 square mile area.  Even though, in parts of Houston, as much as 5 feet (60 inches) of rain were seen while other parts received around 16 inches thus far.



In order to calculate the total volume of rain, the remaining quantity or parameter needed to complete the calculation is the height of rainfall.  According to the news, an average of 40 inches fell on Houston over the weekend.  The proper units needed are cubic feet to complete a comparison of unknown quantities.  Therefore, a unit conversion is needed to convert from units of inches to feet as shown below:

Below is an expression to determine the total volume of rainfall on Houston over the weekend.  Notice that two parameters are needed which can be obtained from above -- Area and Height.

To calculate the total volume of rain, the values from above are plugged into the expression above for volume as shown below:

The total volume of rain which fell on Houston from Hurricane Harvey with an average height of 40 inches is 58.3 billion cubic feet of rain.  Wow!  But how does a reader understand the magnitude of 58.3 billion cubic feet of rain?  As mentioned above, the Dallas Cowboys Stadium was going to be used as a metric.  The interior space of the Dallas Cowboys Stadium is 104 million cubic feet.  In order to obtain the number of Stadiums which could be filled with 58.3 billion cubic feet, a simple division is required as shown below:

WOW!!!!   Now, that is an enormous amount of rain.  And as mentioned above, certain parts received as much as 5 feet (height) of rain.  This would make the number of Dallas Cowboy Stadiums increase.

Conclusion

When a reader or viewer look at two dimensional pictures from the news or online of the massive damage which Hurricane Harvey imparted on Texas, the magnitude is incomprehensible.  Using an analysis can shed light on the disaster.  Of course, nothing is more compelling than being present in the disaster.  The unfortunate damage and loss of life that resulted from Hurricane Harvey is truly astonishing and devastating.  Performing dimensional analysis can help give us perspective to the damage caused by the rain which fell over the weekend.



Now that the damage is done, the repair process is beginning to get underway.  The above analysis can also shed light on the construction process of repairing Houston after the devastation of Hurricane Harvey.  A few readers might disagree with my assessment of understanding.  I would argue that the next time a reader steps into a Stadium, he/she imagines that 560 of these (or even more) were filled and poured onto Houston.  That will drive home the devastation caused by the massive amount of water.  Not to mention the winds which reached up to 125 miles per hour.  Our hearts go out to Texas.  We are with you and watching during this time of recovery.