THE UPSTREAM FACE of the Hindiya Barrage before water from the Euphrates was diverted into the new channel across which the barrage was built. The navigational lock, seen in the left foreground, is 26 ft. 3 in. wide. It is divided by gates into two sections, each 164 feet long. The walls of the lock are of brickwork, 26 ft. 3 in. high and 10 feet thick.
OF the many barrages built by the engineer to control the flow of a refractory river for irrigation, that built by Sir William Willcocks across the River Euphrates, in Iraq, not far from the site of ancient Babylon, proved no mean undertaking. This great retaining wall, one-sixth of a mile long, with thirty-six openings, was built in the record time of two and three-quarter years, in a hot, desert country, at a position far from the base of supplies.
There were no adequate transport facilities to the spot and there was an entire absence of fuel of any kind. There was the difficulty of procuring the necessary labour, for many of the Arab sheikhs dwelling in the region did not look with favour upon the engineer and his assistants who had come to tamper with the flow of their river. The Euphrates, believed by some scholars
to flow through the reputed site of the Garden of Eden, is one of the largest rivers in Western Asia. With the Tigris, which flows almost parallel with it until they meet at Al Qurna, the Euphrates forms the most important river system in this part of Asia.
Rising in the mountains of Kurdistan, the Euphrates has a length of about 1,700 miles. It is a most erratic stream. From April to August every year it is in flood, caused by the melting of the snows on the Taurus Mountains. So extensive are these floods that they reach and even threaten Baghdad, though this city is on the River Tigris and the Euphrates flows nearly forty miles to the west of the city. The Turks built a strong earthen dam right round Baghdad to protect the city from the floods of both the Euphrates and the Tigris. The Euphrates has a characteristic knack of suddenly changing its course, so that towns and villages that once stood on its banks may suddenly find themselves cut off from the river by several miles of marsh and desert. In some instances the stream widens out to a width of over half a mile and encircles large islands, but it is risky for people to settle upon them, as they are liable to be submerged by the floods.
As the average rainfall of the country is only 5 in. or 6 in. a year, Iraq depends entirely on the waters of the Euphrates and on the Tigris for her crops. Everything is grown on irrigated soil - wheat, barley, beans, rice, dates and Indian corn - and with an erratic river such as the Euphrates it means that fruitful regions may, through the river changing its course, become barren and desert.
In Biblical days the country was fertile because of the hundreds of miles of canals, channels and waterworks built by the ancient Chaldeans. These works artificially watered the land, which was the granary of the then known world. The Greek historian Herodotus declares that grain commonly returned two-hundredfold to the sower, and the irrigated areas do so to this day.
HUGE ROLLS OF REEDS were used to dam the old stream of the Euphrates and divert it into the new channel. The rolls, or “sausages” as they were called, were about 60 feet long. They were pushed into the water and sunk in position by weights. Then brushwood, stones and earth were thrown upon them to form a dam about 70 feet wide across the river.
THE BED OF THE RIVER was artificially built up above and below the Hindiya Barrage. On the downstream side a weir, 8 feet wide, was built across the channel. The weir was built on a concrete foundation. The piers of the barrage are built in a series of four steps on the downstream face, reducing the length from 43 feet at the bottom to 36 feet at the top.
Through neglect and ill usage, however, the barrages erected by these ancient engineers had become defective, the canals silted up and much of the land which had not been converted into swamps by the frequent overflowings of the rivers had reverted to a nearly barren condition, and not a little had become arid desert.
This was the state of affairs when the Turkish Government, which then controlled Mesopotamia (as the country was then called), requested Sir William Willcocks to visit the country and advise what could be done. He and his party spent a considerable time, two whole seasons, in this unsettled and barren country, surveying the land between the Euphrates and the Tigris. They had many adventures and the work proved arduous.
It was necessary to survey the country thoroughly and many of the Arab sheikhs were not too friendly towards the English engineer and his assistants, who came along with their instruments taking levels and measurements. A sharp lookout had to be kept to guard the party against any surprise attack. Working in the marshy localities proved trying, for the course of the river is marked with shallows. The existing maps were found to be unreliable.
Sir William drew up a report in which he recommended an expenditure of no less than £15,000,000 on an extensive scheme of barrages, canals and other irrigation works. It was decided, however, not to undertake immediately the scheme in its entirety, but to proceed bit by bit and to build first of all a barrage across the Euphrates to restore a supply of water to the Hilla Channel. This channel serves a large area of land and, passing near the ruins of ancient Babylon, runs to Diwaniya, irrigating a district which is of immense agricultural value.
The engineers of a past epoch had fully realized the importance of providing an adequate supply of water to this district, and had built a barrage across the Euphrates. This barrage, by raising the level of the river, enabled water to find its way down the Hilla branch. Vandalism and neglect had, however, worked their way, and many years ago the old barrage had become so dilapidated that this branch had silted up and the country which it used to serve had become a desert once more. It is evidence of the wisdom of the choice of site for the barrage by the bygone engineers that only some half a mile separates it from that of the new Hindiya Barrage, which is, roughly, 2,500 feet upstream from the old works.
The new works were put in hand in the spring of 1911, and entrusted to the firm of Sir John Jackson, Ltd. Operations had to be carried out in an extremely hot country, where malaria was rife, and many hundreds of miles from the base of supplies. Of transport facilities to the spot there were virtually none.
Soon, however, a busy settlement, with machine shop, factory and other necessary buildings, sprang up near the site. Several thousand Arabs and other natives were engaged as labourers. They were accommodated in huts and tents, and hospitals and isolation camps were also formed. For the European engineers and their assistants, mosquito-proof dwellings were built and ice plants installed.
On the whole the Arabs made good workmen, though their inherent conservatism was inclined to retard the progress of the work. The Arab normally digs up the earth with a kind of scoop. He puts the earth into a bag on his left shoulder, walks away with the bag and tips the earth on a bank. Planks and wheelbarrows were provided. When it was explained to an Arab workman how he could make much better progress by using the planks and barrows, he raised himself erect in a most dignified way and replied: “You people from the West, why, a thousand years ago no one knew you. My people have been here since before the time of Moses. Are you going to teach me how to carry earth?”
Despite all drawbacks the barrage was built across a diversion of the river, the river was diverted for some 5,000 feet and the original channel of the river dammed up. The water was turned into the diversion, a head regulator was built for the Hilla branch and a new channel cut to convey water from the river to a point in the channel above where the silting up had occurred. All this work was carried out between February 1911 and December 1913.
THE RIVERS EUPHRATES AND TIGRIS flow together at Al Qurna. The land between was formerly known as Mesopotamia (“Between the Rivers”); it is now part of Iraq. Ancient Chaldean engineers built a dam across the Euphrates so that its waters would irrigate the surrounding country, which was thus able to produce rich harvests of grain. Near this ancient work the Hindiya Barrage was built across a new bed prepared for the river. Farther north the new escape works divert water to be stored for irrigation purposes in a lake at Habbania.
No portion of the barrage came within the original bed of the river. The dam was built alongside the old river, in the dry. Only when it was completed and the necessary excavation upstream and downstream had been finished was the water of the river allowed to reach the barrage by the demolition of the river bank and the erection of an earthen dam across the river.
The barrage is built mainly of brickwork with a certain amount of cement concrete. The bricks were manufactured on the site. The lime came down the river from the old quarries of the city of Hit. The ground on which the barrage stands was composed of fairly hard silt of such a consistency that when excavated it would stand up to a vertical face.
It was not considered necessary, therefore, to excavate the foundations to any great depth. Under the barrage itself the concrete put in was 3 ft. 3 in. thick and 72 ft. 2 in. wide. These dimensions were maintained for the whole length of the barrage. On this concrete there was built brickwork to a depth of 6½ feet and to a width of 65 ft. 7 in. The upper part of the brickwork was set in cement and the lower part in lime mortar. It was on this foundation that the piers of the Hindiya Barrage were built. The
whole area covered by the works, including the lock through which vessels can pass up and down the river, was enclosed by a complete fence of interlocking sheet piling. Above and below the barrage there was made an artificially built-up river bed, known as pitching. A line of short piling was driven across the centre of the pitching on the downstream side of the barrage. Upstream of the barrage there is stone pitching for a width of 32 ft. 9 in. It is about 3 ft. 3 in. deep and is laid for the most part on clay puddle.
Thirty-Six Barrage Openings
On the downstream side of the barrage this artificially built-up bed extends for a distance of 268 ft. 9 in. The pitching for the first 65 ft. 7 in. is 6½ feet thick. At this point the bed is crossed by the transverse line of sheet piling, and beyond this, for a width of 72 ft. 2 in., the pitching is 3 ft. 3 in. thick. Now comes a subsidiary barrage or weir, which extends right across the channel; the weir is 8 feet wide and is built on a concrete foundation. Beyond the weir is a brickwork apron set in concrete, 57 ft. 5 in. wide, reaching to the outer fence of the interlocking steel piling, the heads of which reach to the top surface of the concrete. Finally comes pitching for a further width of 65 ft. 7 in., taken down to a depth of 6½ feet.
The barrage itself has thirty-six openings, each 16 ft. 5 in. wide. All the piers, except the twelfth counting from either side, are the same width, namely 5 feet, the two exceptions having a width of 11 ft. 6 in. The piers are built in brickwork with the upstream face vertical and the downstream face built with four steps; this reduces the length from 43 feet at the bottom to 36 feet at the top.
The piers are all joined at the top by brick arches, the height to the springing being 19 ft. 8 in. The height to the soffits (under surfaces) of the arches is 23 feet. Above these arches there is a gangway 12 feet wide extending right across the barrage, as well as two continuous walls, 7 feet above the tops of the arches, for carrying the winch for working the sluices. There are two sluice gates in each opening, each gate being 16 ft. 5 in. wide and 7 feet high.
THE HEAD REGULATOR, upstream of the Hindiya Barrage, diverts some of the water into a canal which leads to the Hilla channel of the River Euphrates. The regulator has six openings, each 19 ft. 10 in. wide, and a navigable opening. The canal is three miles long and 120 feet wide at the top. During the building of the barrage and the regulator no water was allowed to reach them.
At one side of the barrage is the lock, 26 ft. 3 in. wide and 342 feet long, with a pair of gates in the middle which divide it into two parts. The effective length of each division is 164 feet. A double rising bridge provides a way across the lock, and it is arranged to come in a line with the gangway over the barrage. The walls of the lock, which are built of brickwork, are 26 ft. 3 in. high and 10 feet thick. The face of the wall on the land side is vertical, but the river face is sloped.
A little upstream of the barrage is the head regulator by which the water is turned into a canal and carried to the Hilla or eastern branch of the river. This canal is three miles long, 120 feet wide at the top and 70 feet wide at the bottom. The regulator has six openings, each 19 ft. 10 in. wide. In addition there is a navigable opening, 26 ft. 3 in. wide. By means of the barrage the ordinary summer level of the river is raised 16½ feet, more than ample to allow a supply of water to be diverted into the Hilla channel. This channel was deepened and cleared for a distance of sixty to seventy miles, as were other canals and channels which it served.
During the building of the barrage and the regulator no water was allowed to reach them. The river flowed peacefully along close by, separated only by a narrow embankment from the new bed which the engineers had prepared for it. This barrier had later to be torn down and the river diverted into the new channel.
It was decided to throw an earthen embankment across the old channel of the river. This embankment is virtually a continuation of the barrage. It was built in a novel manner. The engineers resorted to a plan which for many years had been more or less adopted by the Arabs.
A number of “sausages”, as they were termed, were fashioned of reeds. The reeds were brought from many miles upstream and built into huge rolls on the river bank. The rolls were 60 feet long and 9 feet high. As they were made, so they were rolled into the water, floated into position and sunk by weights to the bed of the river. Brushwood, stones and earth were thrown upon them, and in this way the embankment was built up. This earthen dam is 70 feet wide at the top and is capable of keeping the stream to the new channel.
Some little distance below the great retaining wall is the old barrage built by the ancient engineers. It had long been in a dilapidated condition. Floods had caused a breach in it, making it virtually useless and merely an obstruction to navigation. After the engineers had finished their work they went to remove this old barrage, but the persistence of the Arabs prevented them.
Irrigating Six Million Acres
In addition to the barrage and the regulator, the engineers also carried out an interesting piece of work known as the Habbania Escape. The Euphrates presented a double problem. At certain times of the year the water in the river was not sufficiently high to afford a supply for irrigation purposes, because of the neglect of the old barrages and canals; at other times floods caused serious inundations which converted parts of the country into morasses.
To the north-west of the barrage there is a great natural depression, and it was decided to use this as a storage basin for the flood waters. A canal was cut from the Euphrates at Habbania to this natural basin. Through it, by way of the escape works, water is allowed to pass for storage into the depression known as the Habbania Lake. Here it is held up until the dry season arrives, when it is released and flows along to the river again at a point near Falluja. Normally the water in the lake has a surface area of some 40 square miles. In times of severe flood the surface area of the lake has increased to as much as 300 square miles.
It was Sir William Willcocks’s hope that the great barrage, upon which a sum of £330,090 had been spent, would have been followed by other works until the Euphrates, and then the Tigris were properly brought under subjugation. Sir William declared that it was possible to bring from three million to six million acres of desert land in the Euphrates Valley alone under irrigation.
Funds were not available to carry the work further at the time. Then came the war of 1914-18, which caused the shelving of Sir William’s great scheme to reclaim the land by a great irrigation project.
Since then Iraq has become an independent State. At present she is confining herself to small and immediately remunerative irrigating schemes; but plans along the lines suggested by Sir William are in preparation for several large works of development on both rivers, the cost to be met from oil royalties receivable from the Iraq Petroleum Company, the firm which controls the Iraq Pipe Line, described in the chapter “The Oil Route From the East”.
BUILDING THE HINDIYA BARRAGE across the channel into which the River Euphrates was diverted. The barrage has thirty-six openings, each 16 ft. 5 in. wide. All the piers, built of brickwork, have a width of 5 feet, except for two, which are 11 ft. 6 in. wide.