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Archive for October 14th, 2015

When systems fail

Warning – this is a long-winded and wildly gyrating post with some unsubstantiated assumptions thrown in. Continue at your own risk. All images enlarge.

Still on the storm theme, as the army digs, more questions emerge about the systems to deal with heavy rain.
Systems were in place to carry water away to the sea but what the island experienced during the night of September 21-22 wasn’t a typical event, it was “off the charts”. Building culverts to channel a predictable flow to protect lives and property is a responsibility the government assumes, and the systems were there. However when such a weather event strikes all bets are off.

The tremendous amount of water which dislodged boulders and uprooted trees in the mountainsides was too much for even the best designed, well maintained systems. As did New Orleans with Hurricane Katrina, the island experienced a weather event beyond the imagination (and calculations) of even the most pessimistic engineer.

Normally most water collected from the western slopes of Palouki finds it way to the sea and has done so for many, many years. The confidence in this system led to building near or in mostly dry stream beds all over the island. Instantly, in September, the intelligence of such building was called into question in very dramatic way. This writer spent much of yesterday morning attempting to trace the source of two streams, Kokari (Prassorema) and Tripohti, which were overwhelmed by the flood.
As “Prassorema”, the local name, is called “Kokari” on the maps – we’ll stick with Kokari.

Tripohti and Kokari streams are indicated by blue dashed lines

Tripohti and Kokari streams are indicated by blue dashed lines

From high on the south side of the mountain (550m +/-) Tripohti descends and eventually severs the old Stafilos road, passes through the old dump, and enters the plain at Skopelos Spa hotel where culverts normally take it under the “new” Stafilos road.

Tripohti (Vathirema) above the Stafilos flats.

Tripohti (Vathirema) above the Stafilos flats.


The tripohti stream bed where it passes through the old legal garbage dump cleaned up by the Army.

The Tripohti stream bed where it passes through the old legal garbage dump cleaned up by the Army.


Tripohti and Stafilos Rd junction

Tripohti and Stafilos Rd junction

Kokari’s sources come together on the north side of Palouki in an area called Kafasi and form another gorge close to Tripohti. The two streams run roughly parallel down to an elevation of below 50m where they are supposed to join all the other flows heading towards Vathirema river at Agios Riganaki. Kokari (Prassorema) does not cross the “old” Stafilos road, but follows it.

Kokari (Prassorema) watershed

Kokari (Prassorema) watershed

This is a portion of the  Kokari (Prassorema) stream bed which parallels the lower portion of the Old Stafilos road. Portions have concrete walls as seen. Eventually it hooks up with the watershed system that leads down to Agios Riganaki and  Vathorema

This is a portion of the Kokari (Prassorema) stream bed which parallels the lower portion of the Old Stafilos road. Portions have concrete walls as seen. Eventually it hooks up with the watershed system that leads down to Agios Riganaki and the river.


The photo above shows part of the mess that knocked out the Armoloi pottery workshop and damaged Babis’s boatyard.

This writer has a hunch that a piece of this stream does not cross the Stafilos road but continues down to (and through?) the area where the football pitch has been constructed. That’s what happened in September. The huncher continues, suggesting that since the location of Platanos trees indicate water underground, finding a line of trees might help determine dry stream beds. Or aforked stick or copper based divining contraptions might do the trick.

As we’ve seen most of the water from this basin is supposed to end up in the river either at this point or further upstream (and most likely downstream hidden by concrete).

The old bridge spanning Vathorema. The rectangular culvert on the left, covered by the Ring Road, is supposed to carry water from a previously exposed stream which came down from Aloupi through what is now the small road next to the gymnasium and from there to Agios Riganaki.

The old bridge spanning Vathorema. The rectangular culvert on the left, covered by the Ring Road, is supposed to carry water from a previously exposed stream which came down from Aloupi through what is now the small road next to the gymnasium and from there to Agios Riganaki.

The old or the same Agios Riganaki bridge from the other side.

The old or the same Agios Riganaki bridge from the other side.


Is the opening still the same size as it was 50 or more years ago? One can assume that the concreting of normally perforating land adds to the water load that this river must endure.

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Agnontas 12 October 2015

Agnondas12Oct15
This is a strange composite photo from Agnontas on Monday afternoon. The sea was actually that hue due to westerly winds which stirred the flood mud which had settled on the seabed. With more favorable winds the suspended soil will quickly sink and the water will became clear again.

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