Saturday, September 25, 2010

Paying the poor road tax

Imagine throwing $681 dollars of your money into a hole every year and getting nothing in return. Goodbye hard-earned cash.

Sad to say it but if you drive a vehicle on the crappy streets of New Orleans, that's exactly what you do each year.

A new study estimates that more than half our streets are in "poor" condition--the lowest rating on the scale. Only 13% of roads are rated "good" at the opposite end of the spectrum.

And those pot-holed, dilapidated streets not only make your drives longer and bumpier, they do real damage to your vehicle. Think about it. Rough roads result in more frequent maintenance and repairs, rob your engine of fuel efficiency and even decrease the life of tires.

This damage costs money, and researchers put a price on it. This estimate includes depreciation of your vehicle value, increased fuel costs and the costs of more frequent maintenance. The average annual cost for driving in New Orleans is $681, a figure that is a whopping 70% higher than the US average.

In very real terms, we pay a poor road tax every time we drive on poor streets and highways.

None of us are surprised that streets in the New Orleans area are ranked among the worst in America. If anyone was surprised, it was that we were ranked only 6th in the list of major cities.

The national transportation research group TRIP released its rankings in a report titled, "America's Roughest Rides."

This is a nationwide crisis that everyone predicted. You don't have to be an economist or an engineer to know that roads and highways require continuous maintenance and repairs.

And you probably also know that every year there are more people in more vehicles travelling the roads. Federal Highway Administration data indicate that since 1990, overall vehicle travel has increased 39 percent. So funding of road work has to keep up with the required maintenance of roads that are being used more and more each year.

That has not happened.

A report from the US Department of Transportation estimates the annual investment required just to maintain the status quo condition of streets and highways is $26.6 billion. The actual annual spending on streets and highways by all levels of government: $14 billion.

That's an annual gap of more than $12 billion. No wonder streets seem to be getting worse!

The fix to fix our streets is obvious: dedicate more funding to road work. Government at all levels can pitch in by funding work on streets in the poorest condition. The nice thing about highway projects is that they also create jobs--jobs that can't be exported or out-sourced across the border.

The Federal Highway Administration also estimates that the economic impact of each dollar spent on road, highway and bridge improvements results in $5.20 of benefits in the reduction of vehicle maintenance costs, reduced travel time, reduced fuel consumption, improved safety and even in reduced air pollution.

The full report is here.

Friday, September 10, 2010

NOLA Needs Scenic Canals, Not Grim Levees?

Seriously? THIS is the recommendation of "experts"?

That NOLA needs scenic canals, and not "grim" levees?

Do I even have to do the calculations to refute the idiocy of this suggestion?

Does anyone really believe it's possible to dig enough canals and lakes in New Orleans so that when the next deadly storm surge arrives that water could be safely and efficiently stored to avoid flood damage? This sounds like a plan concocted by third graders--and I apologize to any third graders reading this if that offends you.

Even if we had huge canals and lakes that could contain all the water from a hurricane storm surge, wouldn't they be filled with water all the time? I mean, you can't store more water in a container that is already filled with water, right? So the whole concept would rely upon being able to pump down those canals and lakes to almost empty just before a hurricane storm surge hits us. And then we'd have to devise some way to funnel that storm surge neatly into the canals and lakes before anyone was hurt.

I know we'd all like to think that we don't need those "grim" levees, but friends, there are no other options. I know we'd like to be able to make this hurricane problem go away if we just had more canals and lakes for storage, or just more swamp to knock down the storm surge, or more river diversions to build "natural" defences...

But it just doesn't work.

Okay, so the engineer in me wins out and I will run the numbers just for fun. I know it's stupid but I can't help myself. Let's see what happens if you try to catch hurricane storm surge with canals.

Assume an ordinary hurricane about 9 miles in diameter. Assume it delivers a 3-ft storm surge to the city limits. That's not a very big storm, but let's just see what happens. Assuming a perfectly round eye and a perfectly cylindrical storm surge from the proposed storm, we get about 5.3 billion cubic feet of water.

Let's check my math: volume is pi * r^2 * h = 3.14 * (9 miles * 5280 ft/mi * 1/2)^2 * 3 ft = 5.3 billion cubic feet of water. Check.

Now for storage: assume a typical canal, trapezoidal shape, 20 feet wide at the bottom, 1 on 3 side slopes, 10 feet deep, 80 feet wide at the top. How much can that canal hold? Area of a trapezoid is h * 1/2(b1 + b2) = 10 * 1/2(20 + 80) = 500 square feet.

Okay, so how many miles of canals of that typical shape will we need to be empty and ready to receive that hypothetical storm surge to save our city? Why, it's just simple division:

5.3 billion cubic feet / 500 square feet = 10.6 million linear feet = 2,015 miles of canals.

Yep, that's the answer. Over two thousand miles of canals to store the water from a hurricane delivering 3 feet of water to the city limits. That's a storm many, many times smaller than Katrina. It's a storm smaller even than Gustav.

What if we make the canals bigger? Double the depth--make them 20 feet deep. Okay, so now I'm calculating that we would need 630 miles of canals that are 140 feet wide at the top. Still a completely ridiculous number. It's less than 10 miles from Lake Pontchartrain to the river, so you're talking at least 63 canals crammed into that space.

So how stupid do you have to be to publish an article with the title, "New Orleans needs scenic canals, not grim levees"? It's idiotic to the nth degree.

Now, please, can we focus on building better levees and quit with the artistic and whimsical ideas about protecting our city?

Monday, September 06, 2010

When levees fail, people die

That was the thesis of my presentation this year at Rising Tide 5. I titled it, "When can we get some Dam Safety in New Orleans?" because the title, "Levees should be designed and constructed as life safety systems as dams are," just doesn't have the same appeal to the ear.

During my presentation I used Twitter to share some additional information with the audience. I am repeating those links here for those who may have missed them along with some additional resources.

First, the Johnstown, Pennsylvania flood of 1889 remains one of the most horrific dam failures in US history. The web page of the Johnstown Area Heritage Association includes several survivor accounts and eyewitness reports of the terror that flowed down that day. I read parts of the testimony of Mary M. Butler during my presentation.

Although no one has an authoritative count of the current miles of levees in the US, several have attempted it. I used statistics compiled by the American Society of Civil Engineers as presented in their Report Card for America's Infrastructure. And just as elusive is the number of people who actually live in the shadow of levees and depend upon them for their life and safety. I used a 2006 FEMA report which states that 43% of the US population lives in parishes and counties with levees--still not the number of citizens in peril but probably the best guess.

Federal legislation I referenced in my presentation included:
National Dam Inspection Act (Public Law 92-367) of 1972
● The Reclamation Safety of Dams Act (Public Law 95-578) of 1978
● Water Resources Development Act (Public Law 99-662) of 1986
Water Resources and Development Act (Public Law 104-303) of 1996
Dam Safety and Security Act (Public Law 107-310) of 2002

The eye-witness account from Hurricane Katrina I read can be found along with hundreds of other stories and pictures at the Hurricane Digital Memory Bank.

I mentioned my blog about how dismal 100-year level of protection is and I tweeted this link: 100-year protection is not enough.

I also compared the probability of experiencing the 1% annual exceedence event at least once during a 30-year period--26%--to the probability of disaster while playing Russian Roulette, which is 17%. A better explanation of probabilities and what they mean to the average citizen can be found in the ASCE publication So You Live Behind a Levee! and in this reference from USGS, 100-Year Flood–It's All About Chance.

I concluded my presentation with a recommendation to enact a National Levee Safety Program following the recommendations of ASCE and the Association of State Floodplain Managers. I tweeted this link to the ASFPM publication, National Flood Policy Challenges, Levees: The Double-edged Sword, which captures all the main points of my talk, not just the policy recommendations.

The thrust of my presentation is this: As long as we think of levees as protection for houses and furniture, there will be no motivation to increase the level of protection. Houses and furniture can be replaced and the government underwrites the insurance to cover those losses.

We need to talk about levees as serving a higher purpose: levees are often life-safety structures. When levees fail, people die. That’s what’s important and that’s what we should be designing for.