LAND DRAINAGE BY MEANS OP PUMPS. 5 



driving 10 screws and 5 wheels. These were later supplanted by 

 two pairs of pumping stations, each having scoop wheels and cen- 

 trifugal pumps, all driven by steam, by which means the drainage of 

 the entire tract is now accomplished. 



The great Haarlem Lake of Holland is often referred to as the 

 most remarkable pumping drainage project known. The total area 

 of the tract, which is now surrounded by a canal 37 miles long, is 

 41,648 acres, 3,011 of which are occupied by roads and main water- 

 ways. The work of removing the water in this lake, which was 

 originally 15 feet deep, was completed in 1852, after 39 months of 

 pumping. It is kept drained by three pumping plants of 350 horse- 

 power each, located at opposite sides and at one end of the great basin. 

 The combined capacity of the three plants is nearly 2,000 tons of 

 water per minute raised to a height of approximately 15 feet. The 

 area which was formerly a lake is now traversed by well-improved 

 highways and is occupied by about 20,000 people. 



In September, 1913, the Dutch Government authorized the under- 

 taking of a much greater project. It is planned to dike off about 

 1,000,000 acres of the southerly portion of the Zuider Zee. A little 

 over one-half million acres will be completely reclaimed and made 

 suitable for the production of crops, the remainder will form a reser- 

 voir for the discharge of the River Yssel while the tide gates into the 

 untouched portion of the Zee are closed. The work, as planned, will 

 consume 33 years in the construction and will require an appropria- 

 tion of $130,000,000. The annual revenue from the cultivation of 

 these lands is estimated at $28,000,000 and the population it will 

 support at 300,000. Fifteen steam pumping plants with a combined 

 horsepower of 17,000 will lift the water out of the various divisions of 

 the main district. 



The drainage of large portions of the fenlands in eastern England 

 was originally accomplished by means of scoop wheels operated by 

 windmills. It was not an uncommon occurrence for the districts to 

 be inundated because of the failure of the pumps to operate when 

 required to remove the water. Losses from this cause became so 

 great that the several plants were gradually equipped with steam 

 power, which rendered the drainage of the land much more certain 

 tli an under the old system. 



W. II. Wheeler, in his History of the Fens of South Lincolnshire, 

 states that the entire fens known by that name cover about 363,000 

 acres, that about 85,000 acres arc from 6 to 12 feet below high-water 

 level, and that 12 1,000 acres of this area are drained by steam power. 

 The pump originally used was the large scoop wheel still operated in 

 many of the plants, but tin- centrifugal pump is gradually being 

 introduced as being better suited to the conditions now prevailing. 

 The -.Hue author, iu bis book entitled "The Drainage of Fens and 



