Just when I thought my recent post on the Venezuela drought was dead and buried a comment appeared. It was posted by Miguel Octavio, a physicist by training who lives in Miami but who visits Venezuela frequently, and it linked to a follow-up post on Miguel’s blog that contained a lot of local rainfall and stream flow data that weren’t available to me but which prove beyond any doubt that there is no drought at or around the El Guri dam. This post presents Miguel’s post in its entirety and adds two other items as footnotes:
- A video claiming that Venezuelan authorities are undermining a rockfill dam to supply more water to the El Guri turbines, thereby threatening the dam’s integrity. (Note that Energy Matters cannot confirm the veracity of this claim).
- A revealing Twitter exchange between Miguel and Luis Motta Dominguez, Venezuela’s Minister for Electricity and Energy, who refuses to acknowledge that there isn’t a drought despite all the evidence to the contrary.
Is Drought Really Causing The Problems With Guri Dam?
April 17, 2016
The title of this post may seem strange to some, when you look, for example, at the pictures in this Reuters report, it certainly seems like there is a drought in Guri, except that if the pictures were of the bottom of the now half -dry lake that forms the dam, it is obvious that it will look dead and drought-like in the pictures.
When I was in Caracas, someone told me that they had gone fishing in one of the tributaries of the river Caroni and the water level was quite high, something that was later confirmed by another friend who went fishing in the La Paragua river and saw the water level rise by a meter in a few days.
Despite this, the dam level keeps going down, so, what gives?
Both of my friends deduced from this, that the problem was not drought, but the managing of the Guri dam.
I stored this information in the back of my mind and did not look into this for a couple of weeks, but all of a sudden, this blog post by Roger Andrews came out. While Andrews is not an expert in this particular field, he seems to be someone that likes charts and numbers and understanding problems. What Andrews showed, and I will come back to it, is that this has not been an anomalous year in terms of rainfall in Guri and that the problem with the water level was simply overuse of the dam to generate electricity.
It is useful before we discuss this, to show you an overall map of the area of Guri:
On the left, you can see the overall area in the Southeast of Venezuela down to Brazil and Guyana. In the blow up on the right, you can see the Caroni river and all its tributaries, which is the area that feeds the dam. What matters in the end, is what rainfall is doing there, not in Caracas or Maracaibo or even Ciudad Bolívar, far from the dam, not in the basin of the Caroní river.
What Andrews did, was to look at the data in five rain stations in Bolivar and Amazonas and see if rain was particularly light in the last few years. Here I show two of them: Tumeremo, to the right of the dam, and Santa Elena to the South and which is in the Caroni basin:
As you can see, rainfall in Tumeremo was in 2015 about the same as any other year and in the case of Santa Elena, rainfall levels were at 200 mm per month level, not exactly low given the long term record.
While I could not find a long term record for the Santa Elena Station, I did find the record for Kavanayen nearby:
As you can see 200 mm. is way above the lowest level ever measured.
Just to make sure, Andrews blew out the data and I will show what is seen for Santa Elena:
At this point I wished I had current data for the stations with a long term record to compare. But then, a person I follow in Tweeter (@meteovenezuela) posted the following recent rainfall map:
This is a map of the Caroni river basin above Guri, showing the accumulated rain from March 15th. to April 13th at a number of stations. What is interesting is that we have two stations that we can compared to the long term record: Kavanyen and Uriman. At Kavanayen, the rainfall was 229.1 mm for this almost one month period. This number is way above the average rainfall for April 1st. from 1969 to 1998 in the graph above, which was of the order of 150 mm per month, and we are talking about comparing to the average! Not to the lows…
We can do the same thing for the Uriman station, close to the dam as seen above above, where the rainfall was 151.7 mm in the same almost one month period.
Below is the long term record for this station:
I have placed a red dot on the curve with the data for this year, as you can see, it is right on the historical average, far from being an anomalously low value, as the presence of a severe drought would require.
Despite this, the Guri dam level continues to go down…
And to increase the mystery, I found this plot of the water volume in the Caroni river tweeted by @800GWHMWH:
Clearly, the volume of the river is at levels which are historically high, not low.
I am no expert, I just enjoy looking at data and graphs, I have looked for as much new data to complement Andrews’ and I must say, everything that I have found confirms what he concludes. I do hope one or many of the readers of this blog can help me in getting more information and data and debunking the Government’s claim that this El Niño-induced drought has been anomalously strong, because it certainly does not look like it.
In closing, I show a plot of the peak power demand in Venezuela in the last few years:
Clearly, despite the billions that were invested in order to increase power generation, we are now back to 2007 levels, indicating that something has been going downhill in the grid and I would bet, this has to do with the overuse of Guri, to compensate the decline of the whole network.
—- End of post ——
Footnote 1: The El Guri rockfill dam
In comments to Miguel’s post Eugene Weixel posted this video (commentary in English). It purports to show how excavation at the toe of a rockfill dam threatens to undermine the dam and to place cities and towns downstream in danger of flooding. The video is, however, dated 1980. Anyone with additional information on this subject is encouraged to provide it.
Footnote 2: Twitter exchange between Miguel and the Venezuelan Minister of Electricity and Energy:
(Translation by RA, vetted by MO)
Miguel: Here it is, an analysis by an expert who says there is no anomaly (followed by a link to the Energy Matters post)
Minister: Of course you can demonstrate it …. everyone who follows you will know that you get precipitation data from the web.
Miguel: Precipitation data show that rainfall hasn’t been abnormal
Minister: Miguel, go to the internet and search for rainfall data. It’s what I’m telling you. Don’t deceive! Don’t manipulate!
Miguel: Can you demonstrate that it’s rained less? The problem isn’t that they have generated more electricity?
Minister: You can check it in the Hydrological Bulletin …. It’s not necessary for me to prove it to you.