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Diving Deeper: Episode 23 (May 19, 2010) —
What are NOAA's navigation response teams?

HOST: Welcome to Diving Deeper where we interview National Ocean Service scientists on the ocean topics and information that are important to you! I’m your host Kate Nielsen.

Today’s question is….What are NOAA’s navigation response teams?

Navigation response teams are three-person mobile emergency response units equipped and trained to survey waterways immediately following a hurricane.

To help us dive a little deeper into this question, we will talk with Commander Larry Krepp on NOAA’s navigation response teams. Commander Krepp is the Chief for the Navigation Response Branch with NOAA’s Office of Coast Survey. Hi Commander Krepp, welcome to our show.

COMMANDER KREPP: Hi Kate, thanks for inviting me. I welcome the opportunity to let everybody know a little bit more about our navigation teams.

HOST: Commander Krepp, why did the National Ocean Service first establish navigation response teams?

COMMANDER KREPP: The teams were started as a system of customer response for emergency response surveys. We actually fall under a division called the Navigation Services Division and that division houses the Customer Affairs Branch where we have navigation managers stationed throughout the country, the Coast Pilot Branch falls there, as does my group, the Navigation Response Branch, consisting of our teams regionally spaced.

HOST: How many teams do we have and where are they located?

COMMANDER KREPP: We have seven teams right now. Six of them are small, trailable boat teams. The seventh team is actually the Office of Coast Survey’s research and development vessel. We keep those regionally spaced throughout the U.S. – one in the Northeast, one in the Southeast, one’s there in the Gulf of Mexico and then we have a Southwest and Northwest team, and then the research and development platform is in Lexington Park, Md.

HOST: How many people make up each team?

COMMANDER KREPP: Generally we have three people per team that allows, both for a measure of safety, we have one operator and then we generally have one of the other folks capable of running the boat and then the others do the survey processing and the data acquisition for our work. A lot of our folks are home grown. The type of work that we do is very specialized so we do take folks directly out of college and train them in NOAA hydrographic science and then have them work on the teams.

HOST: Commander Krepp, what equipment do these teams have available to use?

COMMANDER KREPP: Most all of the teams have a core of three pieces of equipment that allow us to do a wide variety of work. The first being side scan sonar. The second being a multibeam sonar and the third being a single beam echo sounder.

HOST: Can you talk a little bit about how each one works and maybe what it’s used for?

COMMANDER KREPP: I’ll start with one of the easier ones to understand and folks that watch educational programming have probably seen anything on shipwrecks, you would probably see somebody talking about side scan sonar. The sonar itself is housed in about a three-foot long towfish we call it and that’s towed behind the boat in most cases. There are two transducers, one per side, and each one of those sends out a beam of sound.

The way that it works, if you can picture yourself holding a flashlight and maybe a pencil on the table, when the light hits that pencil it creates a shadow. The same thing can happen with sound, so as the fish is being towed through the water, our technicians are getting a display on the screen that allows them to see both the objects on the sea floor and because there is a shadow cast we can measure how high an item might come off the sea floor. So that’s the side scan sonar.

The multibeam sonar has multiple beams, that’s where the multibeam comes from. So some of our units have 240 beams, each one when it hits the sea floor and comes back up or an object on the bottom, gives us a depth return so we can in essence code that depth into a color so it can provide us a three-dimensional framework to look at an object.

The difference there is that’s actually measuring depth, that’s not providing imagery per say. And then the final one is the single beam echo sounder and it measures a singular depth below the vessel.

HOST: Alright, so side scan gives you an image of maybe what’s down there based off of the sound waves bouncing back and multibeam would be used for?

COMMANDER KREPP: It provides us the bathymetry, the actual physical measurement of the depth. The other advantage to side scan is that, in most cases, you have what’s called a wider swath so you can actually cover more bottom with it. So even though you’re not getting discrete depth measurements, we can scan an area, a relatively large area much more quickly with side scan and then go back with multibeam and actually provide a detailed height profile on whatever we find on the bottom.

HOST: Very technical it sounds like and I can understand why you really have to train these teams before they’re able to go out and do this response. Obviously there are probably events that require you then to deploy a team to a location since there’s seven teams located throughout the country. What do you need to consider before you deploy a team?

COMMANDER KREPP:The main consideration that we have before we send a team is we need to know exactly what happened in the area. I’m very interested to know if there’s hazardous material, if the area’s safe to put both my technicians and our equipment there. If you folks remember, back in April there was the oil rig explosion and that remained burning for a number of days. For an instance like that, I would certainly be in contact with the Coast Guard and our folks over at NOAA’s Office of Response and Restoration to see what kinds of hazardous materials there are in the area before I sent anybody in.

Secondly, I need to have an idea of what exactly our customer needs. Are we looking for a particular item? Was there a shoal somewhere that we need to better identify and provide more detail on the NOAA chart or to a user?

For emergency response, if we’re talking about hurricanes, need to know the impact of the traffic. If we need the whole channel open or if we’re just looking for a certain area that’s acting as a choke point for any vessels moving in and out of the U.S. port.

HOST: How would someone go about requesting these services?

COMMANDER KREPP: Well generally following an incident, most of our responses are made at the request of either a federal or a state entity, we’re talking about on the national level, the U.S. Coast Guard, the U.S. Army Corps of Engineers. On the local levels, we have state port authorities and state pilot associations. Generally those requests let me know what happened – what kind of data they need to have collected, what kind of a timeframe, is it a true emergency, is it something that can wait a couple of weeks or a month. I evaluate, one, if we have a team available in the area and just try to work it into our standard workload.

HOST: What types of emergencies do the navigation response teams support?

COMMANDER KREPP: As I mentioned before, probably our bread and butter if you will, are hurricane responses. That’s kind of the base of how the Navigation Response Branch and Navigation Services Division was founded. Aside from natural disaster, hurricane-type responses, we do receive various requests from agencies for anything from ship groundings, ship sinkings, we’ve had as a result of Katrina, I believe it was the Interstate 45 bridge that had collapsed, we went and did some surveying for that to identify where some of those pieces are so that they could be removed. Aside from that it’s mostly anything having a navigational concern. The statement that I generally make is our teams are there to respond to anything that has the potential for impacting the marine commerce transportation system that we have in the country.

HOST: Let’s focus a little bit on the hurricane response that you’ve talked about. When do the teams typically arrive on the scene? Are they considered almost like a first responder after an event?

COMMANDER KREPP: They are. Again noting, we do make sure the area’s safe. There is a lot of ground work that we do on this end, up on the headquarters side, to make sure that the folks that I’m sending into that kind of an area, we need to make sure that there’s fuel available, we need to make sure that there’s some type of lodging for them.

We generally mobilize within 24 hours and we’re on scene within 48. We may or may not be able to begin survey at that point, but it certainly allows us to get together and meet with the Coast Guard and the port authority, actually have the people on the ground help direct us to where our services would best be used.

Depending on the track of the storm, there are occasions where we’re able to begin moving a team into an area and in certain instances, when the Hurricane Center’s able to provide me a very detailed track, I can actually move the folks just to the outer range of the damaging winds. We can be somewhat pre-staged to enter an area.

HOST: We talked a little earlier about some of the equipment – side scan sonar, multibeam – what are some of the other tools that your team uses?

COMMANDER KREPP: Yes, there’s kind of two facets to that answer. First off, I did not mention all of the equipment that we use on these boats are tied together via GPS so everything that we find we are able to accurately position. Just getting the imagery doesn’t do any good if we don’t know exactly where what we’re seeing is on the bottom.

We have in the past been able to borrow an autonomous underwater vehicle. It’s an unmanned programmable sonar which we are able to deploy and it can on its own, after we’ve programmed the mission, we call it flying a mission, it actually goes underwater and flies a grid unattended and then that can come back to the surface and then we download it.

The final piece of gear that I use with great success is our Mobile Integrated Survey Team. Rather than having a vessel that we have to trailer, if it’s a truly remote area, we can reach out to the community and request of them a vessel to install gear on. So I have a package, in essence a portable survey equipment package, that I can send out there along with a couple of operators. We can use somebody else’s boat – whether it be a Coast Guard vessel or a Corps of Engineers vessel – and install our gear and survey in a remote area.

HOST: Commander Krepp, what is a day like for your staff responding after a hurricane? Maybe there’s an example, a hurricane from the past, that you could tell us about.

COMMANDER KREPP: Yes, certainly. Probably the most dramatic of our hurricane responses was in response to Hurricane Katrina back in 2005. I’m sure everybody remembers the massive amount of devastation to the Gulf coastal areas. That was a little different for us in that it was a very long response. A good amount of our responses only have a duration of maybe two days to a week.

The Katrina response went on for months and we had multiple vessels in there and there were multiple government agencies. The infrastructure there was pretty well decimated, so it was a fantastic U.S. team effort to one be able to provide the pure necessities of things like fuel, water, food, and shelter for all of the responders down in that area. But we surveyed various ports in conjunction with the Corps of Engineers and were able to relatively quickly establish shipping lanes to allow things to go.

HOST: How do the navigation response teams work with local communities and some of these other agencies following a disaster? What is NOAA’s role?

COMMANDER KREPP: Sure. The scope of NOAA is quite broad. I’d like to narrow it down to the Office of Coast Survey interaction with the local community. Again, within our Navigation Services Division, a branch contemporary with mine is the Customer Affairs Branch and as I mentioned they have actual personnel, regional representatives/navigation managers in each of the geographic areas where we have the navigation response teams. So these folks have a day-to-day interaction with the professionals in the area in the shipping industry and with government officials both on the environmental side and the commerce side of any given port community.

HOST: Commander Krepp, is there a way to measure how successful these teams are?

COMMANDER KREPP: Sure, I think maybe we should divide this into a couple of different categories. One would be the hurricane response and then secondly how we fit into the Office of Coast Survey general nautical charting effort. There are a couple of different measures that I use to indicate our success. In the general survey realm, thankfully we don’t have emergencies happening 24 hours a day, so there is a significant part of our year where I interface very closely with the Hydrographic Surveys Division and what those folks do is they do the planning for all of the routine surveys across the United States. And so for smaller inshore areas, I can actually provide data to them to meet that critical survey need.

And then as we’re talking emergency responses, of course as I mentioned, the whole reason that we’re there is to help reestablish the flow of commerce in and out of a port. And some of those numbers are actually pretty staggering. For some of the major ports, use L.A./Long Beach as one prime example. The average daily value of goods coming in and out of that port is somewhere in the vicinity of $750 billion, so that boils down to about $500,000 a minute moving in and out of the port, so you can imagine that as these ports get shut down, if there was something blocking that waterway keeping these ships from coming in and out, the importance of being able to provide the data to allow somebody to remedy the situation, to allow the ships to continue moving, for every minute that’s clicking by, it’s $500,000 lost to the U.S. economy.

So we can measure the amount of time that it takes the federal effort to get a port open and then estimate from there what the dollar value we were able to save was and of course by us being there, we’re able to opening ports more quickly than could the port open without us. 

HOST: Commander Krepp, in an affected area, who really has the authority to re-open a shipping channel?

COMMANDER KREPP: Sure. In the vast majority of cases, the authority to open a port or close a port lies with the U.S. Coast Guard and the Captain of the Port that has authority over that area or supervises that area. So whenever there is a request for a response, it is a true full-government effort. The Captain of the Port has the authority to open or close the port for shipping, the U.S. Army Corps of Engineers generally has authority within the federally maintained channels, but as we talked about before, the massive amounts of commerce that flows, both in dollar value and volume that comes through these ports, the desire to open channels more quickly becomes very important.

It’s usually those two agencies that call me to add another resource to help open those channels. And so what we actually do is serve the U.S. Coast Guard Captain of Port for the area to provide him data to allow him to make the appropriate decision on whether or not that port is safe, that the waterway is safe for commerce to resume its flow.  

HOST: What is the most unique mission, or maybe the most memorable mission, that a team has responded to?

COMMANDER KREPP: Oh I think, my memory is generally pretty short. All of these, especially hurricane responses tend to blend together, we’ve done numerous hurricane responses and each one of those is rewarding in their own way, just in to know that one, we got in and out of there and were able to help shipping resume in the area.

But in recent history, the small community up in northeast Maine, Cobscook Bay, and when they were having a substantial percentage of their population in this merchant fishing fleet dying. It’s bad enough that these vessels are going down and there are being lives lost, but they also weren’t recovering bodies. So it was very rewarding to me to be able to do a response one not only to help locate the wreckage and assist in providing data for the salvage folks to bring these boats back up, but also help to identify the root cause of what was causing some of these sinkings and hopefully avoid any ones in the future. 

HOST: What would you say is the value of NOAA’s navigation response teams to our non-coastal listeners?

COMMANDER KREPP: An interesting statistic is that for all of the United States whether your coastal or live in the middle of the country, roughly 70 percent of all of the items that you see around you – the earphones that you’re using right now or the speakers that you’re using right now to listen to this podcast, the clothes on your back, the tires on your car all at some point came through one of the United States ports. And especially if we’re talking exports, the middle of the country in the grain belt is very reliant upon timely shipping, getting those goods out of the country, and out to other folks that are consumers of what we export.

So just because we service a coastal locale, there is a massive impact to the U.S. population in the middle of the country.

HOST: Do you have any final words for our listeners today?

COMMANDER KREPP: I would just like to close out this interview letting everybody know and having a chance on behalf of all of the Navigation Response Branch to say thank you for giving us the opportunity to serve the nation. We feel our mission is very important and I hope I was able to demonstrate today the value of the commerce coming in and out of U.S. ports and how we play a role in keeping that commerce flowing. 

HOST: Thanks Commander Krepp for joining us on Diving Deeper and talking about NOAA’s navigation response teams. To learn more, please visit   

That’s all for today’s show. Please join us for our next episode coming in June.