Vagueira beach groundwater: where is the salt...?

Last week one of our students had to leave early because of family health problems, we all wish him a lot of strength for the coming period. The work here continues... We got our water samples transported to Holland and are now concentrating on geophysics and special investigations. So Boris got lucky again and went to the beach yesterday with Jeremy, Diego, Roos-Anne, Inge and Andreas. Not to get more tan or to surf, but to investigate fresh and salt water in the beach soil. We use geophysics to study this and its a nice change from our smelly garbage dump project where we had been the past days...


Today, I got the more demanding task to make a groundwater monitoring well together with Andreas, Roos-Anne and Ingrid. As I am the heavy weight in this group, I had to do a lot of bailing to get the sand out of the well casing, while they turned me around (what's he talking about...?). We got to about 6.5 m deep down to a gravel layer, which forced us to stop. Good for me because I still feel my muscles ache from the heavy work.


Anyway, tomorrow we are going back to Vagueira beach to do some more measurements. Less demanding ones, that is. Geaophysics again and perhaps we'll make a shallow well near the estuary. We expect some rain the coming days and that will give some activity to measure stream discharge and collect rainfall samples.

Posted by Maarten Waterloo

The island study...

Today was a bit of a crazy day. I had to go to the hospital with Diego who had hurt himself while playing soccer yesterday, but it turned out OK. Just a bit of cleaning of the wound on his hand and some anti-biotics. In the afternoon we suddenly had some time to spare and as we had planned to start the island study today, me, Boris and Diego decided to go to the island and install some divers (these measure the waterlevel, temperature and electrical conductivity) in the piezometers that we placed there last year.

The island study is about the freshwater lens that develops on the salt water in the subsoil of the island by infiltration of rainfall. We use hydrochemistry and geophysics to study its development and changes with the tides. Of course, another reason is that it is nice to have a boat trip, work on a small island, get your feet wet and watch the fishermen go by!


Doing this island study involves a trip to the fishermen's harbour in Costa Nova by car, asking one of the friendly fishermen (in this case Adriano) to bring us there and trying to find the groundwater tubes, that were buried invisibly in the sand. The sand was very hot and we danced around a little bit on our bare feet before we found them. We installed the divers and went back to the sea too cool our feet. Then back to Costa Nova for a good coffee. Next visit will be to download the data.

Tomorrow we are going to install groundwater tubes to study contamination of the groundwater from an illegal, rather smelly, garbage dump in a nature area. The things you have to do as a hydrologist...

Posted by Maarten Waterloo

The fonte study...

Yesterday our BSc students started their research. We discussed their projects (they do "fonte" and "small island freshwater lens" studies) and went on to sample the first fonte. Fonte is Portuguese for a water source, or a place where people have public access to water and that is maintained by the city. These are usually natural springs that have been used for ages before piped water became common in the houses. We started out at the Fonte Juncal (see picture below). It gets its water from a pine forest on sandy soil several hundreds of meters away.


Boris demonstrated Inge and Roos-Anne how to calibrate the pH meter an measure pH, measure the electrical conductivity and temperature of the water, analyse for nitrate and bicarbonate, and take filtered samples for lab analysis of chemistry and isotopes.

It was already lunchtime and a lot of old Portuguese ladies, who had been working in the potato fields, passed with bottles to collect water from the fonte. I asked them if they did not have piped water at home. They do, but because that water is treated they prefer the fonte water with their meals, as it has a much better taste. The water quality of this fonte is good, but there are several with high nitrate and I hope that that doesn't give health problems. As these fontes get their water from shallow, non-protected aquifers, they are very liable to contamination (mostly nitrate from use of fertiliser). Good that we do an annual check of the water quality...

Posted by Maarten Waterloo

Sunday is weekend...?

You would think that Sunday would be a quiet day for students and staff alike. But no, at 9:00 am sharp I parked the van in front of the student houses and found two groups ready to leave to start their well measurements. It was a foggy and rather cold start in Barra but the weather cleared up soon enough. I went with Andreas and Diego to install two staff gauges in smaller rivers in their research area.


Arriving at the field site we found out that we accidently brought a temperature logger, rather than a water level datalogger. My mistake. Fortunately, there was a spare one in the back of the van so we proceeded quickly and installed both loggers. The other members of the group managed to measure 10 wells in the meantime and at 12:30 we were ready and hungry. We went to Restaurant Sesta in Covão de Lobo for lunch.

They serve huge plates with very tasty food at a very decent price and I am planning to go there as often as possible. Pity that I can never finish everything that they put on my plate. I left the group (who was planning to continue working the whole day) after having a great Delta coffee. Back to Aveiro, where Boris told me that the two Dell laptops he used had both crashed and seemed beyond repairs. Think twice before buying Dell, unless you like living on the edge! We'll have to share my last Dell laptop now and I hope that it won't give up on us...

Posted by Maarten Waterloo

Installation, the hard work...

Wednesday (30 May) we took our hired cars and cruised around in our research catchments to find good spots to place our raingauges, water level loggers, weather station, etc. It was a really wet day and all the Portuguese we talked to told us that this was exceptional... Good to know but we were still soaked at the end of the day.


The next day we installed our discharge measurement station, Great fun hammering away and getting wet... We also measured the discharge of the river. The girls were suffering from hay fever and could be heard sneezing the whole day. Fortunately, the rain was gone...


We decided to use some of the boreholes that the students had placed the year before and Maarten took us to the spot and managed to find the groundwater tube that was well hidden now in the grass. The GPS was only a few meters off, and your head is a great place to put the receiver.

We picked a spot for the weather station and we made a borehole. It was heavy clay and no water came in at all. Very dissapointing!

On Saturday we got round to doing the meteorology. This took us all morning and we had to skip lunch as well. Lots of attention from passing farmers on small tractors, who laughed at us for drilling a hole in an area that was well known not to give any water. Well, they proved to be wrong and we did find some water in our newly drilled borehole today.



Posted by Maarten Waterloo

The beginning...

Every year, we have this hydrology fieldwork in Aveiro, Portugal, as part of our Master's Programme Hydrology. This is a great opportunity for students to gain practical experience and understand what hydrology is. This year our MSc students were Jeremy Croes, Thijs van Leeuwen, Pieter Pauw, Diego Miralles, Achille Mauri, Ellen Kwantes, Carmen Navarro, Andreas Antoniou, Robert Parinusa and Sebastian Ritter.

As always, the staff, that's me, Maarten Waterloo, and my colleague, Boris van Breukelen, started collecting all the equipment we needed for this fieldwork at our University. This year had been particularly busy for both of us and Boris and I were a bit stressed and hoped that we hadn't forgotten any instruments when we left the University in our big rented van.

Driving to Portugal took us 2.5 days and we were very happy to finally park our van close to our hotel on Saturday morning. Boris is a kite surfing addict and managed to get into the water on Saturday afternoon, even before any of our students had arrived from their excurion to the Algarve. I was just happy with the great Portuguese food.

Our students were all here on Monday and enjoyed the rented houses in the beach town of Barra. On Tuesday we had our first field day. The weather was rather cold, cloudy and we had some rain. We managed to get to the programme and were now all up to date with the local geology and our catchment measurement sites. A good start for the real work...

Posted by Maarten Waterloo

The one left behind

This is a post by the staff member left behind in Amsterdam. I just created a blog for my colleagues in Aveiro. If they do not stop sending me photos of my favourite desert I will block this weblog!

Have fun over there!

Vincent