Models and Mud: Connecting the River to the Model

Finally, I’m near the study site! I’m now in Gisborne, the closest city to the Waipaoa River mouth, and about ~8 hours north by bus from Wellington. I met up with Joey Kiker, another graduate student from East Carolina University on the project. The rest of the crew should arrive by boat later today from Aukland! Today, I got to talk with Greg Hall, a hydrologist (a scientist who studies rivers) at the Gisborne District Council, and picked up keys for a shed we’ll be using for the fieldwork.

Like my meeting with Mark, I was amazed how much exchange can happen in such a short time. Over the last couple years, Greg has been great about sharing data with us. He sends us hourly data for how much water and sediment are coming out of the river and into the ocean. I got to show him how we’ve been using the data – how we put it into the model (we basically ‘place’ freshwater and river sediment into a grid cell that represents the river), what the model does (move water and sediment around based on the laws of physics!) and some of the results from the model (where is sediment eroded and where is it deposited? Does it stay in the area or is it carried away by the currents?).

By explaining what we were doing, I think I left him with a better feeling of the data we’d be interested in. He explained to me the differences between some of the measurement stations (some are more reliable than others). We also talked about the different types of storms that hit the coast in the winter and summer, and how erosion and transport of sediment into rivers changes over time (does type of vegetation coverage in the mountains matter?)

I also learned there is a name for the big flood at the end of January. “That flood that peaked on January 31, 2010” became “Anniversary Day Flood”!

Afterwards, Joey and I went to ‘check in’ to the shed. We are renting it from a seafood company, so we got some truly amazing fish and chips for lunch!