IRRIGATION IN SOUTH AFRICA.
The irrigation of lands by water-channels connected with rivers is accepted as an important means of agricultural development in countries subject to protracted droughts, where rain falls only at distant and uncertain intervals. The irrigation caused by the periodic overflow of the Nile is a noted case in point. But for the annual overflow, temporarily deluging the land for a foot or two, Lower Egypt would be barren instead of a scene of fertility. In a country like England, where there is, generally speaking, too much moisture, the chief consideration is to dry the land sufficiently by draining, instead of flooding it with water; the lesson being thus taught that as regards the culture of soils every country must act according to circumstances. In India, also in Ceylon, there are some remarkable instances of the value of irrigation, and in these countries much more of the same kind requires to be done to avert the horrors of lengthened drought and famine. On this subject, we propose to say a few words regarding large tracts in Southern Africa, which are very much in the condition of those parts of Egypt fertilised by the waters of the Nile.
We speak first of the river Oliphant, which falls into the sea on the west of Cape Colony, and which has various important affluents. The land through which these streams flow is of a most desolate character—broad belts of sand, interspersed with low scrubby bush, swelling into moderate hills, with rugged mountains for a background. Upon the country in the lower part of the Oliphant River rains have no appreciable effect; but when the soil is thoroughly soaked by the overflow of the streams, after the periodical inundations, and then covered by the deposit brought down by the floods from the upper districts, its fertility is wonderful. The average yield is more than a hundredfold. The quantity of land of this character along the Lower Oliphant alone was estimated by the government surveyor in 1859 as eight thousand seven hundred acres.
Thus, like Egypt with its Nile inundations, those districts of Cape Colony—otherwise almost barren—are annually fertilised. But unlike Egypt, the country is unprovided with any means for utilising to the full extent the advantages thus conferred. No appliances are prepared for the purpose of storing the water thus brought down; no artificial channels are cut for directing it and spreading it over a large area; and when the short rainy season has passed, the inhabitants are content to sit down and wait for the next ‘periodical.’
A characteristic story is told by a colonist who visited the locality some years ago: ‘I strolled along the banks of the river, and was much struck with the extremely fertile appearance of the soil, and the very little which had been done for turning it to account. It seemed as if the Creator had done everything for the country, and man nothing. Scarcely any rain had fallen for some time past, and the river had not overflowed its banks for more than a year. The stocks of grain and vegetables were getting very low. The farmer was complaining much about the long protracted drought; and when he had finished, I took the liberty of pointing out how he could, by leading out the stream for the purposes of irrigation, or by fixing a pump to be propelled by wind, on the river’s bank, secure an abundant supply independent of the weather. He seemed to listen with some interest to the development of my plans; and I began to hope that he had decided upon doing something to relieve himself of the difficulty; but eventually, after turning round and scrutinising the whole horizon in the direction of the river’s source, as if in search of some favourable symptom, he yawned heavily, and merely observed in Dutch: “Oh, it will rain some day!”’
Of the Zout or Holle River, the most northerly of the tributaries of the Oliphant, Mr P. Fletcher, the government surveyor, says: ‘By its arteries it brings together the rich karroo soil of the Hantam and Hardeveld and the rich sandy soil of Bushmanland. The best crop of oats I have seen in Africa was in the deposit of this “periodical.” Other portions are of a very saline character. At a rough guess, I believe that in many spots a dam might be constructed three or four feet high, and a couple of hundred feet long, which would flood several hundred acres, thereby rendering them richly arable. I have measured some of last year’s “slick” two feet deep; this, of course, was under the most favourable circumstances; but by the use of dams, the deposit might be regulated, the fresh slick might be allowed to deposit to its full extent, so that in a few years the lands would be out of the reach of ordinary floods, if desirable that they should be so. By this system of irrigation, even the most saline basin would become available to agriculture, and about nine or ten thousand acres on the banks of this one periodical river might be brought under cultivation, which would even excel the richest soil in the “Boland” (upper country).
‘Several tributaries to the Zout River have extensive karroo deposits; some of their basins reaching to nearly one mile in breadth, and their fall being so little, that, standing in their delta, a person cannot sometimes judge with the eye which direction water would flow. Their water-course, which winds through the middle of the deposit, is always well defined, and shews a longitudinal section of the plain. Except in ordinary heavy rains, those channels carry off all the water without overflowing, while a few pounds would leave them in a condition to produce fifty, eighty, or even one hundred-fold. Such is the nature of several tributaries of the Hartebeeste River. I have not seen the latter, but have been more than once informed that it has in some places a deposit of five miles in breadth, that when it does overflow, there is abundance of grass for all the cattle that visit that quarter. If this description of the Hartebeeste River be correct, the products it may be able to yield either in the form of grain or pasture for cattle would appear to most people fabulous. We have here, and not here only, but over an extensive portion of the whole colony, the richest soil in the world lying at present for two-thirds of the year utterly unoccupied, waste and worthless.’
The Hartebeeste is the last principal tributary, from the south, of the Orange River, and rises in the same chain of hills as the Tanqua, one of the tributaries of the Oliphant—namely, the Roggeveld Berg, receiving affluent streams from the south-east and south-west, draining in fact nearly the whole of the central northern part of the colony. This district is at present almost neglected. The chain of hills in fact, which runs from east to west across the centre of the colony, cuts off the northern half from the mass of the colonists, notwithstanding the fact that here is the most fertile land in South Africa.
The Zak, as the upper part of the Hartebeeste is called, is another instance of the wonderful effects upon the soil of periodical inundations. The following particulars are given in Mr Noble’s book on Cape Colony. In the dry season these streams are comparatively small, and often a mere succession of pools; but after rains they run briskly, and where level with the banks, overflow and soak the adjacent flats. In many places so very even is the country that they may be said to have no defined channel, and form extensive sheets of water a few inches deep. The Zak River at two hundred and fifty miles from its source thus varies in breadth from one to four miles; and further on from Onderste Doorns to Leeuwenkop it widens as much as ten miles. Along its course is the most valuable part of Great Bushmanland. Water can be obtained in its bed even when dry, and its valley generally affords pasture to cattle during both the winter and summer months. After floods, there are extensive alluvial bottoms on each side of it, where agricultural products of every kind might be raised. These are now commonly used by the squatters as sowing lands, without any labour or trouble beyond scratching in the seed. One overflowing of the soil is sufficient to insure a crop even although no rain should fall afterwards. The returns are something marvellous, especially those of wheat.
In 1859 the number of Europeans settled on the irrigable portion of the Oliphant was estimated at one hundred and twenty souls. When there was an overflow of the river, they were active enough; day and night they worked incessantly; the sun and the moon alike witnessed that they did not eat the bread of idleness. But talk to them of improvements in the way of artificial irrigation by dams or pumps, and they ridiculed the idea. Such was the description given at that time; and such, with very little alteration, is an accurate statement of affairs now. The population of Calvinia and Clanwilliam, the two districts drained by the Oliphant River, was in 1875, 15,856, of whom only 2046 were classed as ‘urban.’ These figures of course include the natives as well as the settlers; but they represent an enormous advance in population since 1859. It is probable that if measures were taken to secure the permanence of the advantages which are now only temporarily enjoyed, the population and wealth of the districts would rapidly increase.
Of the fertility of the soil without any attempt at cultivation, there are abundant evidences. A sandy plain apparently as barren as the Sahara itself is suddenly transformed into an expanse of waving grass for hundreds of miles, so soon as the annual rains occur. This ‘twaa-grass’ or Bushman grass is an excellent fodder for horses and cattle, which thrive and grow fat upon it in a few weeks: even when dried up in the winter it is better feeding than any available green pasture. The natives scratch in their seeds and leave them to ripen, which they do without the least attention, and whether the country is visited by drought after the summer rains or not.
The principal drawback to the complete cultivation of the lands is the absence of roads or water-carriage. The Orange River, though a magnificent stream, and navigable in certain parts of its course, is blocked by narrow gorges, shallows, falls, and other impediments, and is useless as a water-way. In time probably, it may be made available, by means of inter-communicating canals to enable the rapids, &c. to be passed; but at present the community must look to the extension of roads and railways for the means of fully utilising the produce which would be raised if a ready market could be found. In this respect a decided step has already been taken. A railway of ninety miles in length has been constructed from Port Nolloth on the north-west coast, in Namaqualand, to the upper mining districts, its terminus being at Ookiep. On the most difficult portion of the route the cost has been very little more than a thousand pounds a mile for this distance; and it might be extended further eastward at a still less cost, to the great advantage of the country drained by the Hartebeeste. Another railway, or a good system of roadways, is wanted to open up the Oliphant water-shed; and with these means of carrying away the produce—all that is necessary—the immense natural resources of the district would be fully developed. In the Fraserburgh district, where the Upper Zak river rises, substantial houses, springs, wells, and dams have already been constructed, and plantations and gardens are being extended; but then from Fraserburgh excellent roads run east and west; and the railway to Cape Town comes as far as Beaufort, situated sixty or seventy miles south-east.
Finally, in Great Bushmanland, diamonds have been found; but there are far greater and more permanent sources of wealth than diamond-fields. Sheep and oxen can be raised, and their wool and hides turned to profitable account. Wheat, grapes, and vegetables of all kinds will grow in abundance. In fact, for pastoral and agricultural qualities the country is unsurpassed. Here then is a field for the enterprising emigrant from our own country. Capital alone is wanting for its development; and capital however small, judiciously expended, must be at once remunerative. We are glad to be able to add that an Act has been passed by the Cape Parliament for granting facilities to landowners for obtaining by loan or otherwise the means of improving their lands by irrigation or other similar permanent works.
Other districts prove how the colonists have succeeded in turning what was, more really than Great Bushmanland or the Lower Oliphant can be said to be, a ‘howling desert’ into valuable farms, by opening up springs, making dams, forming irrigation channels, and planting trees where no trees existed, and where water was only an occasional and very ephemeral visitor. There is no reason indeed why the ‘Nile lands of South Africa’ should not rival in productiveness the great ‘world’s wonder’ in the north of the continent; after which, from natural circumstances, they have been not inaptly named.