Popular Science Monthly/Volume 60/April 1902/The Draining of the Zuider Sea
|THE DRAINING OF THE ZUIDER SEA.|
By Professor J. H. GORE,
GOD made the world, but the Dutch made Holland' is a saying quite common with people who visit the Netherlands; and as one looks upon the great sea dykes that keep the North Sea from sweeping over North Holland or the smaller dykes that hold the rivers within their channels, it is easy to see that the retention of the land created is possible only with great vigilance and care. Lakes have been drained and their beds converted into arable land, useless bends have been taken from the rivers and the ground, once covered by marshes, has become fertile gardens. The map of Holland shows many changes, not only in the coast line, but in the water covered areas within.
The draining of the Haarlem Lake was looked upon as a marvel of engineering skill and patient industry, but the work here discussed is far greater in magnitude and presents technical and economic difficulties never before encountered.
A clause in the constitution of the United Netherlands permits the organization of new provinces. However, when it was written, there was in mind the possibility of rearranging the eleven provinces in such a way as to enlarge the number. The acquisition of territory of any considerable area was not thought of until 1848, when it was proposed to drain the Zuider Sea, which, if accomplished, would add a province somewhat larger than Zeeland.
In 1892, Queen Emma appointed a commission, consisting of the Minister of Water Affairs and twenty-nine members to consider the general question of converting this shallow inland sea into agricultural lands. Two years later, a very elaborate report was submitted, in which the problem was discussed from every conceivable standpoint. So many questions were raised in this report and so much discussion was provoked that it was not until last summer that the people generally realized what the Commission actually proposed and how the work was to be done. The air has been sufficiently cleared to enable one to assert that while it is universally conceded to be possible to drain as much of this sea as may be desired, there remains the feeling that while the cost of this undertaking is certain, the benefits are by no means sure.
It is proposed to build a sea dyke from Ewijksluis in North Holland over the island of Wieringen to the Frisian Coast near Piaam, a distance of 24.8 miles, the cost $16,000,000 and to require nine years to build.
This route was selected because it would be possible to construct the locks in the solid ground of the island and, though not the shortest line that could be selected, it would be in the shallowest water and so far south that some of the streams flowing into the sea would have their outlets outside of the district to be drained. Along the top of this dyke it is intended to have a railroad, thereby shortening the distance by rail from North Holland to Groningen by 35 miles—a matter of considerable importance in a country where no distances are great.
By shutting out the North Sea, the water left in the Zuider Sea would be fresh, and it was feared that this change would cause the death of the vegetation along the shores and that sickness would result from its decay. But the freshening process would be so gradual that there would be abundant opportunity for an adaptation of vegetation to the changing conditions. The entire scheme contemplates a step-by-step process. That is, after completing the sea dyke, so that the inflow of water can be stopped and the outflow regulated by the use of the sluice gates, it is proposed to surround in the northwest corner of the imprisoned sea about 52,620 acres and from this pump out the water. As fast as the land within this dyke should become free from water it would be subdivided by ditches like the rest of Holland and placed under cultivation at the earliest possible moment. It is believed that this can be done in five years and that the cost would be about $5,000,000.
The portion of the sea to be included in this, as well as in other polders, the name given to drained areas, has been determined from many thousand borings, and also from the desire to avoid stopping up or diverting any of the larger streams that now empty into the sea.
After putting this polder in good shape, the southeast corner will be dyked in and the water pumped out, yielding ultimately 249,000 acres. This will require ten years and the cost is estimated at $24,740,000. After this shall have been completed 77,800 acres will be enclosed in the southwestern section of the sea. The work of converting this into arable land will require four years, and cost $9,140,000. The last section to be drained will be in the northeast, where $125,649 acres will be added to the domain after five years' work at an estimated cost of $14,000,000.
The polders have been selected so as to leave undisturbed every important city now on the sea, and also to allow all the rivers to empty into the part of the sea not included. The plan also contemplates the deepening of the mouth of the Ysel, the broadening of the entrance to Amsterdam, and the improving of the outlets of all the rivers now emptying into the Zuider Sea, in this way bettering the condition of all the harbors, placing the canals under better control and converting the remnants of the sea into a body of fresh water, so that in case of overflows the land will not be damaged as it is now.
By doing the work in this piecemeal fashion, covering thirty-three years, only 24,000 acres will be added annually. This can be brought under cultivation without causing any disturbance to agricultural conditions in the country or affecting the markets of foodstuffs. Then too, by the gradual draining of the sea the fishery interests will not be suddenly imperilled, and persons now engaged in fishing will have time to adjust themselves to the new conditions.
Heretofore the littoral rights have been the most difficult to adjust. The people realized that many of the cities of Holland have been 'built on herring bones,' that the fishing fleets were the schools in which so many Dutchmen had learned the sailors' trade, and that it was on the sea that Holland won her greatest victories of peace as well as of war. The Commission, therefore, made a close study of this question. They ascertained how much money is invested in the Zuider Sea fisheries, how many men are employed, and what the annual catch amounts to. They learned that the investment was less than had been surmised, that many of the fishermen spent only a small part of the time fishing and that acre for acre the egg sales in the Haarlem polder exceeded the fish caught from the Zuider Sea. However, it is understood that some must suffer in being obliged to change their mode of earning a livelihood, and provision is made for lending assistance. All persons having vessels large enough to engage in the North Sea fisheries are to be exempt from harbor dues when returning with a catch; all men over fifty-five years of age who are now devoting the greater part of their time to fishing will receive a pension, and the smaller craft will be purchased by the State.
When this new province becomes a part of the Union, it will be divided into districts of the most approved size, with ground reserved for schools, churches, cemeteries and town halls.
But it is not intended to sell the land thus acquired. The interest on first cost and the maintenance is all that is asked of the occupants who become perpetual lessees of the ground. This amounts to an annual tax of about $7 per acre. The rentors are to erect their own buildings and be subject to the usual rate of asssessment on all personal property. Inasmuch as land in the Y polder rents for twenty dollars per acre and some for even more, it is thought that the price here expected can be easily obtained.
Dividing up the sea by polders and building a sea dyke across its mouth will lessen the dangers from storms and overflows and diminish the cost of maintenance of the long dyke that now fringes the entire sea. By leaving open water between the polders where the deepest water is now found, there will be no impeding of intercourse between the larger cities that now enjoy boat communication.
One would expect to see the financial features well considered. The Commission asks the State to pay annually $758,000 for 33 years, and to raise this amount by the issue of Zuider Sea bonds of 100 florins (about $40) each. These bonds to be sold in the open market or given in exchange for deposits in the Postal Savings Bank. The bonds are to yield 2.6 per cent, and be legal tender in payment for ground rent. No one sees any difficulty in this plan of procuring the means. Dutch credit is good and the State finances have been so well managed that since 1850 the public debt has decreased by an amount in excess of what is deemed necessary to carry out this great plan.
The plan is not only feasible from a financial as well as from a technical standpoint—it is almost a necessity to the State. At the present time only 56 per cent, of the land is cultivated by the owners, and the number of small farms—less than two acres, has increased at the rate of 2,072 per year during the past ten years. The demand for land is so great that rents are growing larger with the result that less surplus food stuff is available, and the people are therefore affected by the fluctuation in foreign markets. Then too the country is annually losing 5,000 of the strongest inhabitants who are forced from home in search of work.
In the immediate future a large proportion of these people could find work in the draining operations and, as the lands become available, the surplus population that must now seek homes in foreign lands, could find land in their own country and that, too, close to Amsterdam, its best market.
Holland has suffered more from storms on the inland waters and inundations therefrom than from the seas that skirt her coasts. The drying up of the Haarlem Lake removed one great source of danger and loss, but immunity will not come until the Zuider Sea, which has been a constant menace since 1440, yields her 787 square miles to the tillers of the soil.
The Dutchman is especially fitted for work of this sort. He calmly sits down, reckons up the cost of the undertaking, devises means and appliances and then proceeds with the work without troubling himself whether it will require one year or twenty. He does not expect to play the part of Canute and command the waters to recede, but ever conscious of the inroads that the sea has made upon Ms country, his work is sweetened perhaps by a feeling of revenge that he will reconquer all that has been lost and levy tribute for the 371 lives that were lost in 1885 by the breaking of some of the dykes.
The Government is willing to appropriate the requisite money just as soon as the finances will permit and entrust the work to a contractor, knowing that every one of the 1,250,000 piles needed for the sea dyke alone will be put in place and that not a hundredweight of the 70,000 tons of basalt blocks will be missing. The Dutchman is so loyal and feels so much national pride that no imperfect work is ever found in Government contracts.
An idea of the magnitude of the work can be formed by glancing at a few figures.
The sea dyke will be 24.8 miles long, 114.5 feet across the top and 21.6 feet above high water; the river Ysel is to be carried out into the sea a distance of 10.5 miles with a width of 948 feet; the entrance to Amsterdam must be widened by two miles; dykes around the polders will be necessary having an aggregate length of 198 miles with an average height of 11.4 feet; in the Island of Wieringen, 30 locks will be required, 33 feet wide and 16 feet deep; an encircling canal must be constructed from Enkhuyzen to Uitdam, a distance of eight miles; the sea dykes on the Frisian coast must be heightened at a cost of $240,000 and four pumping stations with an aggregate of 16,930 horse power must be installed.
Though the undertaking is great, the entire commission agreed that it should be done, and twenty-one out of the twenty-eight believed that the State should be in control rather than to grant the concession to a private party. When finished the State can issue another medal, like the one minted to celebrate the draining of the Haarlem Lake to bear the inscription:
"Zuider Zee, after having for centuries assailed the surrounding fields, to enlarge itself by their destruction, conquered at last by the force of machinery, has returned to Holland its invaded land." And the historian of the work will close his account of the material gain to the State by saying: "But this is not all; we have driven forever from the bosom of our country a most dangerous enemy; we have at the same time augmented the means for defending our capital in time of war. We have conquered a province in a combat without tears and without blood, where science and genius took the place of generals, and where polder workmen were the worthy soldiers. Persevering to surmount the obstacles of nature, and those created by man, the country has accomplished, to its great honor and glory, one of the grandest enterprises of the age."