INTERNATIONAL SIMPOSIUM

Transcription

1 INTERNATIONAL SIMPOSIUM 1996 WATER CONDUCTION FOR INFLATADLE HOSE IRRIGATION Inn. Raul Valdez Lopez PLHSTOZn RGHOPLHSTCOS V SERVICIOS MEXICO

2 s i m p o s i u m internacional 1996 ENGINEER RAÚL VALDÉZ LÓPEZ. PLASTOZA AGROPLASTICOS Y SERVICIOS MEXICO. In the agriculture of many countries, the technological development in the use of water has determined the application of measurements that increase the productive levels per unit of area and immediately decrease the operative and technical deficiencies. In Mexico the main sources of agriculture of water are superficial and subterranean, depending greatly on drippings underground natural water mantles and infiltration accumulation. This availability is also subject to rain and the annual distribution in different parts of the country. The exploitation of the superficial drippings with the hydraulic infrastructure existent in our country has a storage on capacity of 120 km3, which only 49 km3 are used to satisfy many consuming demands including those of the agriculture. In subterranean waters, the average of natural accumulation in 459 water bearings plus the endrafted water is of 63 km3 with the annual drawing of 24 km3 in 140,000 subterranean deposits plus 30 in explotations over the 20% in 80 water bearings found in the north, northeast and Lerma-Balsas locations. The agricultural needs of these volumes of water are of 61.4 km3 for an area of 6.0 millions hectares, dividing into 3.3 millions of irrigation districts and 2.9 millions of medium watering units. This area which represents 30% of the water destined to the country's agriculture, generates approximately 50% of the total domestic value of production. 1

3 It is important to underline that of the volumes used for agriculture it is estimated that only 40 km3 per year are used for irrigation, 12 km3 return to the accumulation deposits in approximately 10 km3 of water are lost in piping and evaporation. Flooding, and mainly gravity, are the methods used in 92% of the total irrigation areas. During 1994 it was estimated that the average piping efficiency was a 64%, 70& with the parceling method and a global efficiency of 45%. C0NSIDERRT10NS Regarding the above mentioned and exclusively piping, the used of water in a parcel level generally dealing with the actual hydraulic infrastructure, focuses in a major percentage of water wasting as a present in past reality, this adding to the following agricultural side factors, like as follows: 1.- Overexplotation of water bearings. 2.- Low o non-existing maintenance in keeping of hydraulic structures and installations. 3.- Non-adequate application of irrigation methods. 4.- Low technology irrigation methods. 5.- High undergrowth of weed proliferation favored by agricultural returns bearing an ecological and economic consequences. 6.- Low cultivation productivity and income yield capacity. 7.- High agrochemistry consumption. 8.- Lack of application of the Federal Law of Waters. 9.- Producer and official sector indifference Little transference of technology to the field Meteorological phenomenon as droughts and freezing Decrease in sown and reap areas. It is necessary, nevertheless, to notice the efforts of many private and organized producers, on new irrigation methods and systems in a reduced agricultural area distributed in the country, with some impacts in its application of water and agrochemistry which represents approximately 38,000 hectares with sprinkling, micro-sprinkling, dripping,etc. The forward considerations lead us basically to 85

4 solve the problems of the use of hydraulics. One of the most important is the lost by piping and evaporation tending to be more efficient near'the source of supply, to finally deposit it in a correct measurement and frequency to each plant of the obtained cultivation, in this way it's higher productivity, combined with all of those factors and elements the intervening from the planting up to its harvest. Of course, each agricultural area defines its own necessities for planing and installing of an irrigation system and the application of methods that can primarily reach the requirements. Currently, the different pressurized irrigation methods are known, they make more efficient the used of water found by the plant and these will depend greatly in the income yield capacity of the cultivation and the economical situation of the producer or company. But in the methods of irrigation by gravity, we basically depend on this effect for the movement and transportation of water. HLTERNHT! VES We can count with the following alternatives for the transportation of water for agricultural irrigation land: 1.- Coating of channels with a plastic film, concrete, stone, etc. 2.- Rigid piping of PVC, aluminum, steel, etc. 3.- Inflatable pipes of polyethylene, ultravinilone, cotton, butyl, etc. We can combine the application of these pipes with holes and floodgates of different diameters for wateriness that can eliminate the use of traps, depending on the conditions of each land. INFLATABLE PIPING for such effects, due to its easy handling and economic transportation of irrigation water. Within the alternatives available in the market, we have developed the POLYETHYLENE FLAT PIPING APPLICATIONS FLHI PIPING APPLICATIONS The inflatable plastic hose is an alternative to obtain an excellent use of the sources of water for its transportation as much as for agricultural or farm animals use basically. * AGRICULTURE.- The transportation of water from a well, pool, channel, etc., to the place where it will be irrigated, it's done connecting the hose and guiding the water with a previous prepara- 1

5 tion of the land, or using former channels, crossing over open or harvested land. * LIVESTOCK.- Mobilization of water from weir to weir or weir to drinking place. CHflRflCTERISTICS OF THE INFLATABLE FLAT PIPE OR NOSE The inflatable hose is produced by extruding polyethylene and U.V. absorbers with yellow, white and blue pigmentation color. diameter of the hose by 2", that is, for a pump of 5" (50/60 L/seg) put a hose of 8". This condition is also observed in pools where the inlet is totally open. 2.- When it's connected to a principal or secondary channel, or pool, it is important to bear in mind the outflow of the inlet to decide on the diameter of the hose, and this way be able to control the total expenditure and not have problems in irrigating changes or an extra pressure that can cause bursting of the piping. The thickness of the film has a 1000 caliper (250 thousandths). This caliper has a limitation in its resistance against the pressure it undertakes, in its handling as much as in the transportation of water coming from wells, pools, channels, etc., which would be exclusively for the movement of water by gravity, as described later on. 3.- The couplers either for connecting to channels or in the joint of pieces of hose, depending on the diameter, can be done with PVC connections available in the market or elaborated with galvanized rolled sheets, or use plastic containers or buckets, strongly binding in its union. You can also stuff one hose into another 3 ml. hose towards a slope without the use of couplers. When a inflatable hose is used for transportation from a well or pool, principal or secondary channel, it is necessary to consider the following limitation aspects: 1.- In the case of a well sources with a pump, it is recommended to increase the It is important to connect the hose to the inlet in the same level, thereby allowing a light downward inclination but avoiding its hanging that could strangulate and rupture its. 4.- The inflatable hose is for the CONDUCTION OF WATER IN A DOWNWARD FLOW, NOT FOR THE PRESSURE and for the column of water to 87

6 be move, it requires a minimal inclination, without exceeding 3.0 per thousand. In conduction's with a lengths higher than 500 ml, it will bcnecessary, if the inclination is larger, to put respirators at the beginning and every time that they exceed a minimal inclination of 1.0 ml. These can be done using tanks of 200 liters with and outlet of the same diameter of that of the pipes, which could help to control and level the pressure and trapped air. 5.- When connecting the hose, it should be stretch out mechanically or manually, avoiding that it remains twisted or taut. To avoid the aside rolling and strangulation of the hose when water flows through it, it is necessary to put a grille, with an one third of diameter, in a little ditch. 6.- Left the water slowly flow, when we are talking about sources such as channels or pools, to be aware of its correct flow and its terrain adaptation. In the case of a direct connection to a well pump or gallery, you should be aware of the aspects of its installation. 7.- At the end of the conduction, you should never tie the tip of the hose, use a tank of 200 liters and put the hose thereon, this would you let to control your portions of irrigation. 8.- In the turns of a 900 maximum put the pipes in such way that these can flow freely, without strangulation's, and towards a downward inclination. In the market there are a lot of accessories for regulate the expenditure to the parcel, eliminating the irrigation by means of trap. These accessories are adjustable floodgates with a fixed insertion of 2", mobile insertion plugs, fixed insertion floodgates and perforating devices for fixed expenditures. Whichever you opt for, will depend on the type of cultivation, require expenditure, irrigation arrangement and most of all on the economy. Depending on the method applied for irrigation, the type of floodgate will determine if the watering hose would be fixed or movable, that is, some producers like to leave the watering hose fixed and others have inlets to a determinate distance, depending on its irrigation outline to connect the watering hose with floodgates and move along when the irrigation is done. The placing of the adjustable floodgates is easy and quick. It just need to have a placing or perforating device that is coupling to the valve with the filled tube, place the floodgate at the beginning of the flow of water to control the expenditure. With a slight, but firm stroke, introduce the clamping ring and close clockwise. 1

7 The different diameter plugs are placed on the filled hose stroking slightly with a perforating device, and can be removed whenever irrigation is needed. The inflatable hose, depending on the caliper or thickness of the film, it is not possible to determine its resistance since there are many factors such as the self handling in the field, storage, transport, etc. Therefore, it will depend greatly, on the previous preparation where the hose will place, transporting or irrigation changes, etc. RDVRNTHGES I D DISHDVHNTRGES Because of its application and duration characteristic, the plastic inflatable hose is of low cost, initially, compared to other systems of irrigation, considering the volumes of water used, nevertheless, we specify the following advantages: 1.-Water is transported with an excellent profitability. 2.-There are no water lost by infiltration's and evaporation, as it happens in channels or ditchs. 3.-Less lost by friction in the conduction. 4.-Less application of pesticides and labor since they eliminate the channels or ditchs. 5.-Quick installation and collection. 6.-N0 need for a large storage areas for its protection. 7.-More opportunities of irrigation with the same water flow coming from wells, channels, etc. 8.Traps are eliminated with the use of floodgates. 9.-More control through the watering at any irrigation schedule. 10.-Less cost per lineal meter for water's conduction. 11.-Application through the conduction of agrochemicals. The advantages above-mentioned are the most outstanding, however, it is necessary to consider its disadvantages: 1.-Less lasting live compared to other types for conduction, such as aluminum, PVC, steel, etc., piping. 2.-It is necessary to replace at the end of its useful life, which is a maximum of two years exposed to photodegrdation. 3.-Requires care when handling. 4.-It can be attack by rodents, so requires protection of the livestock. 5.- It can only be used to transport water through gravity or discharge. 89

8 simposium international 199B AGRICULTURE OSE Due to is versatility, the inflatable hose can be used with the installation of adjustable floodgates, plugs or perforating devices, and also in the transportation to various cultures, such as alfalfa, prairies, vegetables, fruits, etc. CONCLUSIONS M any great actually problems in explotation will be solved after the adequate use of agricultural water. world, in spite of Mexico's storage capacity, hydraulic infrastructure, great irrigating agricultural area and proximity to the beginning of the millennium 2000 exists for over 30 years. This transfer should be dynamic and modernized. We have a very valuable resource: WATER THE MOST EXPENSIVE WATER IS THAT WHICH WE DO NOT HAVE H H H g ^ B Central pivot $ 7, years Side roll $ 6, years Dripping (Tape) $ 1, TAPE: 05,Eq.: 10 Manual aspersion $ 4, years PVC 8" Floodgate $ 9, years Polyethylene-coating Channel $ 3, years Concrete-coating channel $ 8, years Polyethylene 8" Floodgate $ 3, years The use of the polyethylene inflatable hose is another alternative within many of the actual irrigation systems. It is not possible that only a few years ago, the transference of technology to determine productive sectors started, whereas in other countries of the