FROM WASTE TO WEALTH.

Auckland Star, Volume LIX, Issue 164, 13 July 1928, Page 15

FROM WASTE TO WEALTH.

PROFITABLE UTILISATION or SEWAGE. MLLilUlitXt" METROrOLJ l-\:. . ..iJ.M. (By PLOUGHSHAi;K. i What is justly claimed to be nut of the examples in the world ( ,f disposal on ail economic ba>N is to be found in the extensive farm operated at Werribee by the Melbourne and Metropolitan Board of Works. Here a tract of light, inferior grazing country, with a decidedly inadequate rainfall. ha> been converted into pasture «o rich that it carries a beast to the acre throughout the winter, and it is found a difficult matter to keep breeding stock in lowenough condition. The Metropolitan farm is situated about twenty miles from Melbourne, on the gently undulating plain that lies to the west of the city and extends from the foothills to the shores of Port Phillip Bay. Unirrigated, the plain is a poor grazing proposition, with an indigenous herbage of barley-gra>s and danthonia.

and a carrying capacity that varies from rather over fine sheep in a favourable season to .\*-her less tliau nothing at all in a dry one. A certain amount of cereal hay is grown, \ut with an annual rainfall of less than l.'in dry fanning not hold out manv inducements.

The Metropolitan Farm was started in the 'nineties and has bec.n gradually extended each year, until the total area is now 22,tj00 acres, of which StiOO acres have been specially prepared for sewage irrigation and sown to pasture, and 1200 acres of reclaimed foreshore are used for winter and flood-time irrigation: the balance i« n»rd mainly as a "run-off" for over-fat stock. though with over 7000 new hoii-e- being connected each year in the city it is found necessary constantly to tnlarge the irrigated area. Some idea of the immensity of the undertaking can be obtained from the fact that the amount of sewage now bandied is well over 3o million gallons daily, and that Melbourne i< adding to its population at a rate equal to two or three good-sized country towns each year. Steam Tackle for Subsoiling. The underlying soil varies somewhat, there being in place* areas of stiff, puggy clay, but the greater part of the farm carri/« a topsoil of loam about loin deep overlying a strata of stiff clay approximately a foot thick: beneath this again comes a porou- loam. To allow free drainage for the immense quantities of liquid poured into the soil it U neeessary to prepare the land by breaking through the clay strata, and so facilitate percolation from the top-»oil to the porous underiying formation. For this work a set of Fowler -tea in - tackle is employed, a pair of 4."> h.p. engines working a heavy reversible rigidtine cultivator on the cable system. The cultivator penetrates to a depth of ."10in without bringing to the surface any ui the raw clay. At one time deep ploughing was practised, but the pre-ent system is found to give far more satisfactory results. A few hundred acres of oats are grown each year for hay. and as a covercrop for lucerne on the dry land, but otherwise all cultivation work is directed towards the preparation of the land for permanent pasture. The general lay-out of the farm commands admiration. A fall, from the supply main to the outlets, of 10 feet per mile is obtainable, which means that the greatest care must be exercised to ensure an adequate flow. The greater part of the irrigated area is laid out in rectangular blocks half a mile square and bounded by roads and shelter belts. Alongside these are the carriers and mains. Each block is further divided into sub-blocks 10 by 20 chains, each of which ha* a minor carrier and drain. There are nearly *>00 paddocks on the farm, each of which is well provided with shelter, access and a constant supply of fresh water. Method of Irrigation. A strict rotation is practised. About •500 acres are treated with sewage each day at the rate of 3in of liquid. After a day's irrigation the paddock gets a week's spell followed by a fortnight's grazing before, another irrigation i« given. Each block thus gets sixteen irrigations in the year. Each acre takes the effluent from approximately 100 houses, and it is noteworthy that the water discharging into the drains is so perfectly flltejed by the soil that it is purer than any creek or river as it leaves the farm. The principal constituents of the pastures are ryegrass and prairie grass. Other grasses are being tried out, but great caution has to be exercised as the irrigation forces them to an extraordinary degree, and even high-quality grasses such as meadow fescue tend to become coarse and tufty. The older pasture shows a good proportion of white and strawberry clovers, but these do not seem to establish well until the paddock is 6 or 7 years old: possibly the grading of the surface brings too much raw soil to the surface. The strawberry clover is particularly appreciated on account of its high palatability and strong winter growth. Strangely enough, subterranean has not proved a success. The colour and density of the pastures is a revelation and there is little doul>t that were dairying permitted by the authorities this would be some of the finest cow country in the world: the constant production of lush, quick-growing feed would be ideal for milk production. The Live Stock. With so much of interest in the way of pastures and general management it is difficult to do justice to the cattle and sheep to be seen all over the farm. Beef cattle constitute the most important item. The studs of Shorthorns, Herefords and Polled Angus are among the best in Australia and figure largely at the Sydney and Melbourne shows. The Algfue stud is headed by a New Zealand buy and resort is had to the best Australian and imported blood for the purchase of sires. The grade cattle include 3000 breeding cows that are mated with registered bulls, and from 5000 to 6000 store cattle are purchased each year, some of them coming from as far afield as Queensland. The condition of every beast is a tribute to the excellence of the pastures. Even the cows become so fat that the calves are weaned as late as possible in an endeavour to reduce their dams to calving condition. _

• 1 1■ 1! 01'* IM i'■ Sheep are not an important feature, as the land is too rich to make breeding an easy matter. Hve thousand ewes are lambed each season and many thousands of ...tore- are bought for fattening. 1 iie ewe thick includes 1200 stud Rom-

i:ey ewes of an excellent type: this season these ewes, averaged a return of -$•»/ apiece, lambing !>7 per cent and < lipping lOJlb of wool, sold for an average price of 19H1. a remarkable tor Rotnney>. In addition to the cattle and sheep large numbers of citv Horses

are grazed, there seldom being le-s than 11)00 head on the place. In view of the tact that the unirrigated area is of unceitain carrying capacity, it is evident that the irrigated portion must bo stocked to the extent of well over a ben-t to the acre, winter and summer, yet there is seldom any shortage of feed and very little hay i> saved.

•Tu-t whether it would pay any of the laiger cities in New Zealand to embark on a similar scheme rs open question, but it is doubtful whether Melbourne ha■— ever made a better investment. I'alctila i ed over a peri rid of 20 years, sewage disposal has cost the citv less than tkl per person, and it would be difficult to imagine a more efficient or less otFensive means of utilisation. The farm now pays all expenses with the exception of interest on its capital value of a million pounds, a considerable sum. but an infinitesimal one compared with the cost of operating other methods of sewage disposal tor cities of over a million inhabitant*. The farm carries a resident population of 0.50, with one of the best health records in Australa. pays wages at (it\ fates, and gives its emplovees excellent living conditions.