Chapter Twenty Seven

Repair of Derbendikhan and Dokan Dams

After the report was completed I kept a close watch on the operation of the power stations and made frequent visits. When I found that the water level of the reservoir had exceeded the safe level set by Binnies by 4.27 metres. I was very upset and had a long talk with the Station Superintendent. I pointed that the increased stress on the unreliable gates was now a factor of two and a half times the stress allowed by Binnies. He replied that prior to Binnies inspection the water level was allowed to go up as far as 5.5 metres over Binnies safe level and the gates held. Furthermore, he said that infrastructure below the dam, including some bridges, would be swept away should the spillway gates be opened. It was obvious that his mindset as an utility engineer would not allow him to release his precious water with its immense electricity producing potential. This mindset made him oblivious to the risk he was taking in the event of a dam collapse. While he recoiled to the risk of opening the spillway gates on the basis of losing a few bridges he was prepared to accept the risk of flooding Iraq, with a high fatality potential in the event of a dam collapse, by not opening them.

I insisted that the gates be opened and eventually got Hogar Shalli (The Kurdish office manager of UNDP/UNDESA in Sulaymaniyah) to call the PUK Prime Minister, Kosrat Rasul Ali (Kosrat Rasul Ali was a member of the Communist party and is now Vice-President of Kurdistan). We explained the position to him and he instructed the station superintendent to open the gates. In fact, he opened one and the waters continued to rise. The following day he opened the second, and eventually he opened the third and last gate. This gradually reduced the high level. This illustrated the pressures on the station operating staff. They wanted to get the last watt of energy from the water behind the dam for their impoverished country and were prepared to take enormous risks in exceeding the permitted water levels.

No work had been done on providing power standby to the spillway gates either. To cut a long story short I acted on a hunch and after further prolonged questioning of the station superintendent I discovered that they had the standby motor/generator in their stores. Communication was difficult as the languages involved technical English, Arabic and Kurdish with sometimes non-technical translators. Parts, costing $1,000 in his estimation, were all that was needed to put it into operation. These were procured in Jordan and the work was put in hand. After a number of further visits to the station it was obvious that the station staff did not have the resources to do the work and my staff would have to carry it out supplemented by outside contractors when required. Then I contacted UNDESA in New York and told them that the Debendikhan spillway gate anchorages would have to be completed by Binnie and Partners.

Regarding the cavitation problem, I asked UNDESA to appoint an outside company immediately. It was most urgent as the leaks had got much worse. The leak reported by Binnies had been sealed but the repair had broken down and the leak was now much bigger. The dam engineer had said that he was now frightened of it. As regards risk management this man was to the right of Attila the Hun. When a risk-taker like that says he is frightened people should take notice. As the work could only be done in the summer months when the water was low the work should start immediately otherwise the station would have to face the winter and spring floods in a very vulnerable condition.

When I visited Dokan Dam I was not surprised to find a similar state of affairs there. There was no spillway gate problem at Dokan. There the overflow was catered for by three spillway tunnels and the emergency overflow problem was catered for by a Glory Hole Bell Mouth Overflow that was very similar to the overflow mechanism of a common toilet cistern. Again I contacted UNDESA and told them that most of the work would have to be contracted to outside consultants and contractors and the sooner the better.

Water being released from Dokan Dam Spillway.

Photo courtesy of U.S. Defense Department Multi-National Division – North Public Affairs Office.

In the event the work was eventually taken in hand. Technopromexport of Moscow carried out the work in Dokan and the work in Derbendikhan was carried out partly by my UNDESA consultants and partly by our friend, George Hallowes of Binnie and Partners. The UNDESA consultants were largely composed of engineers from SMEC (Snowy Mountains Electricity Company) of Australia and HECEC also of Australia. Malcolm Scott of HECEC, a very experienced Hydro Power Station engineer performed nothing short of a miracle when he addressed and overcame most of the remaining difficulties in Derbendikhan. George visited the site a number of times to organize the repair project, finally arriving with his team and equipment for three months to do the work. He made a number of monitoring visits later to ensure that all was well.

George Hallowes (bespectacled) describing the work on the spillway gates to visitors. Note the water plume to the left as one of the spillway chutes is discharging. The upward ski slope curve at the bottom of the shute is to turn the water upwards and away from the dam, so that it would dissipate its power in the plunge pool and so prevent damage to the river downstream from the dam. Mr. Aziz CEO of Erbil Electricity Authority is second from the left.

The release of water down the slipway chute was an awesome affair. The sight of so much water rushing down the slipway without going through the turbines was heartbreaking in a country so bereft of power. Being a former utility engineer myself I could understand and, to some extent, sympathize with the Kurdish engineers’ reluctance to adhere to the Binnies restriction on water level. However, it had to be done to avoid the catastrophe of the collapse of the dam. It was so spectacular that it used to be released for visiting dignitaries such as Benon Sevan, Assistant Secretary-General in the UN Department of Political Affairs and head of the United Nations ‘Oil for Food Programme’. When he visited the dam I was asked to brief him on the situation there. This I did and left nothing to his imagination.

The awesome power of the released water from the Derbendikhan spillway.

The land slippage problem was solved by clearing out the deep pits that had been sunk into the side of the mountain. These pits were sunk to the underlying rock and were equipped with powerful pumps to pump out any water that would seep from the surface to the rock face thus forming a liquid layer between the base rock and the surface soil layer. The surface layer would slide on the rock base and trigger a massive landslide and so block the intake to the power station turbines. Due to lack of any maintenance these pits were choked with silt that had to be cleared out. This had to be done by hand. Some unfortunate labourers were lowered into the pits and had to remove the silt with buckets. This was most unpleasant work with the surface temperature at >40oC.

A Kurdish workman standing in front of one of the pits.

All the surface area around the dams was dangerous with unexploded bombs and shells. The area had to be thoroughly de-mined before any work could proceed. The de-mining operations usually turned up a number of unexploded ordnance and underlined the danger of working in such places. When the tailrace (a specially designed channel to take the exit water from the power station without damage to the river banks or bed downstream) was being dredged (deepened) by the UNDP team, to increase the potential head on the turbines and so increase the station output, a military truck was rescued from its watery grave. Such were the joys of working in Derbendikhan. This work was greatly facilitated by Salam, the former CEO of the Sulaymaniyah Electricity Company, who procured and organized all the excavating machinery providers. The work on the Draft Tubes was almost as unpleasant as the work on the Land Slide Pits but was eventually completed by Malcolm Scott and his helpers.

Working on the cavitation problem in one of the Derbandikhan scroll cases (Protective cover for the turbine and its workings). The draft Tube is accessed from here and one of the turbine blades can be seen inside reflecting out. The work on the Draft Tubes was almost as unpleasant as the work on the Land Slide Pits but was eventually completed by Malcolm Scott and his helpers.

When the water level was lowered in the summer months it was possible to install a layer of rocks on the inside wall of the dam. These were to trap any debris from sinking to the bottom of the dam berm and clogging up the turbine intakes.

The lift problem was taken in hand by a young Kurdish Lady Engineer who eventually got them working. Lady engineers are highly respected in Kurdistan and are very competent.

The construction of the draft tube gate operating hoist support structure was a frightening affair. The shuttering for the massive concrete support columns and the reinforced concrete hoist supporting beam was supported by a dense network of bamboo scaffolding. Remember the gates weighed a total of 120 tons.

I asked Noel O’ Regan, then in Ireland, to source some divers to inspect the Inlets to the Turbines in Derbendikhan and to determine the state of the intake gates and the extent of the reservoir sedimentation. Eventually we decided that it was too dangerous and opted for ROVs (Remotely operated vehicles) with cameras instead and established that sedimentation was not a problem.

The ‘hammer and sickle’ flag on the wall of the road leading to the top of Derbendikhan Dam signals that it is a safe distance from Baghdad and Saddam. This view is reinforced by the size of the guard of Peshmergas on top of the dam and their understated firepower. The flag also is a relic of the Kurds flirting with the Iraqi Communist party in the war with Saddam, Talabani’s socialist leanings and, of course, the period when Moscow protected the Kurds from Saddam. No doubt it was also a compliment to the PUK Communist Prime Minister, Kosrat Rasul Ali.

As the work progressed Derbendikhan became a ‘must see’ stop for the myriad of fact-finding missions that descended on Kurdistan from UN in New York as well as the routine visits from dignitaries from Baghdad. It often hosted visiting TV crews from all over the world and the Kurdish authorities were no slouches when it came to using threats to achieve whatever was a priority for them at any particular time. “If you don’t do whatever we require” they would intimate “we will give you a very rough time when we are interviewed by Japanese (or whatever country was visiting at the time) Television next week.” When the UN was involved with these hydro stations the combined output of the stations was 300 MW. Now 10 years later it is only 400 MW from stations with a nameplate rating of 649 MW. However, the cloud had a silver lining. I had made the Dams safe.

Group visiting Dokan with the UN Res. Rep. Odeh. They are from left Mohammed Rasheed a Baghdad driver (his brother was in the Muhabbarak), Odeh’s Driver (He was arrested by the Muhabbarak for alleged smuggling) a local UN Sulaymaniyah driver in the background, Vivienne, a Palestinian aide to Odeh in UNDP Baghdad, Ms. Kareem a Kurdish aide to Odeh in UNDP Baghdad and Showne an electrical engineer working for UNDP in our Sulaymaniyah office. She was formerly Head of Distribution Department in the Sulaymaniyah Electricity Company. Her young brother had been arrested some years previously in a random street round-up by Saddam’s police. They did not see him again. Some years later the family was informed by the police that he had died.