Nancy Byrne






Kiera Coffee: Can you describe what a hydrographer does?

Nancy Byrne: We collect underwater data and present it to engineering and architect firms, to dredgers, and construction people. Mostly people want water depth surveys or images of the bottom. And some jobs have to do with tides and currents and water quality. We do that too but most of the time, clients want water depth.

KC: How do you survey water depth?

NB:  We go out in a boat and we need to know how deep the water is so we use something like a fish finder only it’s the survey version of a fish finder, for water depth. And then we need to know where we are, so we use a GPS to find our position. Basically we drive around collecting data. We end up with a file that has times (we use that for tides, because we have to subtract tides). We bring it back to the office and edit out all the bad data points, like if a fish swims under the transducer that’s not real, we have to get rid of that.


KC: On your website you mention something called acoustic monitoring.

NB: There was a bridge being built on the Housatonic River and the state started a program about protecting fish ears.

KC: Fish ears?
NB: When they’re building a new bridge they’re driving big steel piles in, and hitting them with basically a giant hammer. It makes this loud kerchunk. So if fish are close enough, the sound damages the little hairs in their ears. I did a study to find out how loud the noise was.


KC: Did you grow up around water?

NB: I did. My dad always had a little boat so we’d go out all the time. Our house was right on a river and we played there and in the creeks, in the swamps, we did things we weren’t supposed to do like ride ice floes in the winter.

KC: Really?

NB: Till we got caught.

KC: How far did you go?

NB: Not far at all. We had sticks and poles and would go like a thousand feet and then get off and run home.


KC: Have you ever had to be rescued on the water?
: No, no. But we did rescue a guy, a jumper who was being chased by thugs. We were on the Hackensack River and there were guys sort of waving from a bridge. People always wave at us, they want to know what we’re doing. So we waved back but they were really frantically waving so we slowed down. They pointed and there was a man hugging a piling. He was in the water in March when the water is absolutely the coldest. He was not wearing a coat or anything so he had like five minutes before he drowned (you lose your muscle and then you can’t hold on to anything). Anyway we had to go up to him kind of gently so we didn’t squish him, and try to grab him. When we were almost there he leapt for our boat but he couldn’t swim because his muscles were shot. We were able to get him and he flopped onto the deck. His friends ran off the bridge and onto the shore, they were waving us over. We told the guy, ‘We’re bringing you to your friends on the shore.’ He said, ‘No no, they’re after me!’ So we reversed to go back out into the middle of the river. I was thinking, are they going to shoot us? They were yelling from shore, ‘Get over here!’ And we were saying ‘No!’  It turned out the guy was a bridge tender and he had called the police, but I think he owed a debt to someone and they were collecting so they chased him and he ran and jumped off the bridge. We waited for the police to arrive, and brought the guy to them.

KC: That sounds hair-raising.

NB: That’s not a normal day; usually our biggest problem is finding a place to launch.


KC: Is it rare to have a woman-owned hydrography company?

NB: It is. I was the first female to be certified as a hydrographer, in 1990.

KC: Why aren’t more women drawn to it?

NB: More and more are, but most engineers I run into are men. Most contractors I meet are men, I don’t know why.


KC: You list something on your website called discharge dispersion mapping.

NB: That’s a really fun job, it is one of my favorite things. If you own a sewage treatment plant, the treated water gets dumped back out into the nearest body of water. Even though it’s treated, it’s still a little icky, so the state has regulations on how much you can discharge. The plume can only go a certain percentage across a river and it has to dissipate within several hundred feet downstream. If you want to build a new pipe or change your discharge, you have to get a new permit, have a study done.

KC: So you do that study.

NB: Yes. There’s a fluorescent dye and it is super concentrated; one drop will color a swimming pool red. We pump in this dye, usually from the plant, and we calculate parts per billion. Then we go out into the river and map all the tides and we show how quickly it disperses. We drive around getting data until we get the whole plume and it disappears. And then we stop and wait for slack tide and we do it again.

KC: Why do you especially like this?
NB: You get to be like Beaker from the Muppets. You have to calibrate, so you have all these beakers to measure, and you mix the solution to get the right parts per billion and then you have to run your equipment through to calibrate it. Then we get to go to the plant which is always fun, go inside to see how all these things operate and we get to set up big giant barrels of sticky red dye. We get to set up the pumps and watch them for a while and measure again to make sure they are pumping at the exact rate. Usually we let it run twelve to twenty-four hours before we do the survey. So it’s fun.


KC: Your website also mentions sub bottom surveying.

NB: That’s when we go into the sediment. A depth sounder just reflects off the top of the sediment but we use a lower frequency that penetrates into the mud. We use this data to tell an engineer, oh it’s really soft mud and its about three feet thick and then below that is a hard gravel sand.


KC: Given all your time on the water, when you go on vacation do you like to go somewhere on the water?

NB: If it involves driving a boat, I don’t. If it involves swimming I do.


KC: When did you first learn of hydrography?

NB: I stumbled into it. My brother worked at an oceanographic company and I had just graduated from music school.

KC: Music school?

NB: I don’t know why, at the time I thought music would be a good profession for me. But I finished school and I just worked where my brother worked and thought, This is what I love. I went back to school for science.

KC: It’s interesting that you and your brother are both drawn to this kind of work.

NB: Yes, but now he fixes submarines.

KC: What instrument did you play?

NB: I played trombone, I was going to be a trombonist in an orchestra.

KC: There are studies about the connection in the brain, between math and music skills.

NB: My favorite class at music school was 17th century composition. Which is all math. There are rules, like this always follows this, this is pleasing to the ear and is what you expect. So it’s completely math.

KC: Do you have other siblings that work in related fields?

NB: I had a sister and we worked together for years. We were called the sonar sisters.


KC: Technology is such a big element in your work; it must have been really different in the past.

NB: Hydrography was a new discipline when I started. The guy who trained me said that when he started, if people wanted to know water depth, four of them would go out in a rowboat and toss the lead line out as the boat was moving, and when the boat caught up, when the line was plumb, one guy yelled out the reading and another guy wrote it down. And then for position they would use natural ranges on shore? I don’t know what they did.

KC: It’s a different job now.

NB: The GPS today is really cool; you get centimeter accuracy in three dimensions, fifty times per second. But when you work, you still have to compare data against an existing disk. There are disks all over, with elevations, and northings, eastings. You want to make sure your equipment is working, so you calibrate against them. A lot of times it’s like geo-cashing to find the disk because maybe it was set in 1920 and everything’s changed but you have to try and find it. It’s kind of fun.

KC: So the disk is a physical thing. And it can really be from that long ago?
NB: Yeah, I mean it may be updated with its position, and there are more recent ones put in… but sometimes we see them from the 1920s. A lot were also put in in the 1970s.

KC: How do you find them?

NB: You go online to the national geodetic survey. There are little dots on the map and you find where you’re working and you click on that and it gives you this sheet that describes the disk. It’s a little piece of history; the description starts when the disk was set, which could have been the 1920s. It will say something like, “Put in at Mr. Brown’s barn cupola down the dirt road.” And then it is updated, so the next entry might be from 1950: “Yep, we found the disk in good condition. Mr. Brown doesn’t live there anymore, it’s so-and-so family.” And then you’ll get one from 2014, “Found it in good condition. Description good. “

KC: I feel like when you retire you can be a treasure hunter, you have the right skills.

NB: I would love that!

photo credit: Matunuck, Rhode Island