surface irrigation system

iv. From results already available, the required intake opportunity times, rreq, needed to apply a depth of 8 cm (Zreq) were about 389 minutes and 679 minutes for initial and subsequent field conditions, respectively. In Surface Irrigation, water is applied and distributed over the soil surface by the help of gravity. An effort will not be made to develop a design procedure for irregularly shaped basins or where the advancing front is very irregular. If the advance associated with the maximum flow is too long, then either the required application should be increased (at the risk of crop stress) or the field length shortened. Three major types of surface irrigation are level basin, furrow, and border strip. Compute the required intake opportunity time, rreq, as outlined previously. Compute a revised estimate of the depletion time, T2: 5. One method of minimizing tailwater is to reduce the furrow inflow when the advance phase is completed. The computation proceeds as follows: Since the application efficiency will vary with Qo several designs should be developed using different values of inflow to identify the design discharge that maximizes Ea. Utilizing Eqs. Analytical model for furrow irrigation. Sub Surface Irrigation. In: J. Feyen et al. Consequently, a wider range of furrow flows needs to be examined along with their performance characteristics. Adjust Wo until Nb is an even number. Thus, the design procedure does not need to search among various flow rates for a value that meets a design criterion like finding the deep percolation-field tailwater trade-off point. Initial field surveys showed that the fields needing first attention were comprised of a loam soil, sloped 0.8 percent over the 100 m direction and 0.1 percent over the 200 m direction. Then the irrigator with some simple instructions from the designer can 'share' this flow among the appropriate number of furrows and achieve a reasonably good approximation of the optimal discharge. The field layout can be found by trial and error or calculated. As is shown, the differences in bay elevations correspond to the head on the outlets needed to provide the desired advance phase flow and the wetting flow simultaneously. The details of the computations are already given in the calculations of the previous example. Analytical model for border irrigation. The time of cutoff, tco, is found from Eq. = .76] of the distance between curves K* = 1 and K* = 3 yields
The eventual selection will be the one with the best performance over both infiltration conditions. Other studies analyzed surface and subsurface drip irrigation systems in T urkey (Y azar et al ., 2002). 32. Design procedure for furrow cutback systems, 5.4.3
Rawls, W. J., Brakensiek, D. L., Elliot, W. J. and Laflen, J. M. 1990. The application efficiency of furrow irrigation systems can be greatly improved when tailwater can be captured and reused. The depth of water at the end of the border, yL, will be: viii. The rreq for the first irrigation is 214 minutes and for the subsequent irrigations it is 371 minutes. Water is in short supply so the project planners would like an estimate of the potential application efficiency with and without cutback and reuse. It cannot be used unless this condition is met. In: R. G. Allen (ed. This service is more advanced with JavaScript available, Sustainability of Irrigated Agriculture In any case the tailwater reservoir and pumping system need to be carefully controlled and coordinated with the primary water supply. Dimensionless advance trajectories for borders and furrows having an infiltration exponent a = 0.3, Figure 52c. If the individual furrow inflows are set at .042 m3/min, two sets can be irrigated simultaneously to have effectively a 3 set system, and, the number of furrows in the first is: The volume of the runoff reservoir needs to be 493 m3 and the capacity of the pump-back system must be 1.02 m3/min. The design should provide an advance phase flow sufficient to allow tL = rreq. Evaluation of HYBRID model for simulating water flows in closed end sloping borders for design and management. 1988a. Yen, B. C. and Riggins, R. 1991. border design example
The Qo verses tL data are plotted in Figure 60. Surface irrigation systems can be classified into three major types: basin, border, and furrow systems. Gradient search technique for land levelling design. Compute the advance time for a range of inflow rates between Qmax and Qmin, develop a graph of inflow, Qo verses the advance time, tL, and extrapolate the flow that produces an advance time equal to rreq. This perspective dictated the analysis that follows. The upper limit on the number of sets can be evaluated by examining the duration and frequency of the irrigations. Surge irrigation: 1. I. These systems should be flexible to irrigate fields adequately in which the surface roughness and intake rates vary widely from irrigation to irrigation. Schmitz, G. H. and Seus, G. J. Crops can be covered by water over long periods due to the soil’s texture and infiltration rate. Benefits and costs of laser — controlled levelling — a case study. basin by basin, border by border, etc. To the extent the basin is rectangular, its largest dimension should run along the field's smallest natural slope in order to minimize land levelling costs. Other systems enter the picture as one moves from country to country. It will therefore not be necessary to regulate the pump-back system during the first irrigation to a value different than that for later irrigation. Storage facilities for effluent must exist for extended periods of time when the ground for subsurface irrigation systems is wet or frozen. 1990. By today's standards, these losses are large and it may be cost-effective to add cutback or reuse to the system to reduce these losses. Surface irrigation is the application of water by gravity flow to the surface of the field. At its simplest, no attempt is made to stop fields from naturally flooding.In general, this is only suitable in situations where the crop is of little value, or where the field will be used only for grazing or even recreation. Choosing six sets as the basic field subdivision, the number of furrows in the first set is: For the first irrigation, the volume of the runoff reservoir must be: Recalling that for a first irrigation condition, the time of cutoff is 278.5 minutes, the capacity of the pump-back system is therefore: The number of furrows per set for the subsequent sets is: There are 200 furrows in the field. Initial Design Calculations. Surface irrigation optimisation models. of design
open-end border systems, 5.5.2 Design of blocked-end
Compute a revised estimate of rreq, T2: 3. Izuno, F. T. and Podmore, T. H. 1986. Soils appear to be relatively non-erosive and have been tested to yield the following infiltration functions: Later Irrigations Z = 0.0053 r .327 + 0.000052 r. Z has units of m3/m of length/m of width, and r has units of minutes. 32 found as part of the advance calculations. Water use variability in irrigated level basins. 99: Finally the application efficiencies of the alternative flows and flow directions are found using Eq. It is divided into 13 chapters, with numerous illustrations, diagrams and photographs. Design procedure for furrow cutback systems
vii. Yu, F. X. and Singh, V. P. 1989. Field evaluation procedure for surge irrigation. Basin irrigation is favoured in soils with relatively low infiltration rates. If they are within about 0.5 minutes or less, the analysis proceeds to step 4. In a long field, this time can be substantially less and therefore a more efficient use of cultivation and harvesting implements is achieved. 56. Real time estimation of furrow infiltration. In: Dedrick, A. R., Erie, L. J. and Clemmens, A. J. This book describes, evaluates and outlines common problems in surface irrigation. Equation 50 contains two unknowns, tL and r, which are related by Eq. Similarly for the later applications, rreq = 371 minutes. The interested reader can refer to several references in the bibliography for other graphical techniques which extend beyond those given here, but as one does so, it becomes more important to understand the nature of the hydraulic assumptions. Dimensionless advance trajectories for borders and furrows having an infiltration exponent a = 0.4, Figure 52d. 48 for furrows and borders and Eq. In: R. G. Allen (ed.). The one important constraint on the cutback flow is that it should not be less than the intake along the furrow and cause dewatering at the downstream end. A process for improving the performance of irrigated agriculture. This need not be the extensive evaluation that is needed to actually move the earth. 2. Talk to an irrigation surveyor and designer or other irrigators with SSD irrigation. Among all the irrigation systems in this list, surface irrigation is the least vulnerable to climate considerations such as heavy wind or rain. ; and. Holzapfel, E. A. and Marino, M. A. The results, shown in the table below, indicate that one good design is to divide the field into 4 individual subunits or sets of 50 furrows and utilize an inflow of 0.018 m3/min per furrow during the first irrigations. vii. the topography of the land with particular emphasis on major slopes, undulations, locations of water delivery and surface drainage outlets; iii. J. Katopodes, N. D., Tang, J. H. and Clemmens, A. J. Not affiliated 5. Mechanisms by which surge irrigation reduces furrow infiltration rate in a silty loam soil. Seasonal evaluation of surge flow irrigation for corn. The soils are relatively stable so assume the maximum flow velocity could be as high as 13 m/min. The number of furrows in subsequent sets is 79. Compute the inlet flow area, Ao using Eq. Experimental. However, the general situation is that fields must be broken into 'sets' and irrigated part by part, i.e. Now the system must be configured for the later irrigating conditions. The following table gives a detailed summary of selected options for the first and subsequent irrigation conditions running in both the 200 m and 100 m directions. which is a cutback of 43 percent of the advance flow. Equation 48 is used with L and .5L to find the appropriate values of Ao. In principle, the design of surface irrigation system was designed some parameters so we get a chance infiltrate relatively uniform from the base to the tip of the land. Recession and depletion are accomplished at nearly the same time and nearly uniform over the entire basin. This information can be used to solve for the time of advance, tL, using either of two procedures: (1) the volume balance numerical approach; or (2) the graphical approach based on the advanced hydraulic models. In Jordan valley project, application efficiency was 64% in surface irrigation and 91 % in drip system for vegetables (Battikhi and Abu-Hammad, 1994). Humpherys, A. S. 1989b. A semiautomation of basin and border irrigation. Rendón, L., Ortiz, J. and Acosta, R. 1991. This flow, of course, must be less than the maximum non-erosive flow. Surface Irrigation Systems. The computation of depletion time given above is based on the algebraic analysis reported by Strelkoff (1977). This makes the job easier. The application efficiency, Ea, can be computed using Eq. The design question at this stage is which one leads to the optimal design. Again Mannings n can be 0.04 for initial irrigations and .1 for later irrigations due to crop cover. As a final thought in this section, something should be stated regarding costs associated with surface irrigation. Kemper, W. D., Trout, T. J., Brown, M. J. and Roseneau, R. C. 1985. The time of cutoff for each set during the first irrigation was determined previously as 7.1 hours (428 minutes). The result after two more iterations is 21.9 minutes. On the other hand, good judgement is no substitute for the mathematical aids presented herein. Surface irrigation: Surface irrigation is mainly used in field crops and orchards. At the end of this procedure, the minimum flow will also have been identified as that which fails to complete the advance phase in a set time, 24 hours for example. Dimensionless advance trajectories for basins having an infiltration exponent a = 0.3, Figure 53c. If the layout is calculated, one approach is to fix a furrow flow and determine the external supply that is needed. Adopting water conserving irrigation technology; the case of surge irrigation in Arizona. Dimensionless advance trajectories for borders and furrows having an infiltration exponent a = 0.5, Figure 52e. (eds.). The Problem. This minimizes earth movement over the entire field and unless the slopes in the direction normal to the expected water flow are very large, terracing and benching would not be necessary. Error = ABS (T2 - T1) = 75 - 70.33 = 4.67 minutes. An engineer may have an opportunity to design a surface irrigation system as part of a new irrigation project where surface methods have been selected or when the performance of an existing irrigation system requires improvement by redesign. ICID, New Delhi. Furrow advance using simple routing models. Furrow firming for control of irrigation advance rates. Furrow irrigation performance in reduced-tillage systems. 96 - 98: e. Since T1 is not close to T2, steps b - d must be repeated with T1 set equal to 677 min: e. Again another estimate of td seems to be required by the difference found between the iterations. The design intake opportunity time is defined in the following way: where Zreq is the required infiltrated volume per unit length and per unit width (and is equal to the soil moisture deficit) and rreq is the design intake opportunity time. Figure 57 imposes this layout on the field. Skogerboe, G. V. and Shafique, M. S. 1990. The application efficiency of later irrigations would be about 59 percent. Humpherys, A. S. 1989a. During later irrigations, both borders would be irrigated simultaneously with the water supply. Furrow irrigation flow rates, cutoff times, and field layouts, 5.3 Computation
Surface Irrigation Systems. Disadvantages of Surface Irrigation. The problem. This is usually difficult if the water supply is being supplied by an irrigation project. It is worthwhile emphasizing that the time of advance, tL, associated with a furrow inflow, Qo, must be less than the required intake opportunity time, rreq, in order for the cutback scheme to operate properly. = 0.50 for an average of 0.52. Dimensionless advance trajectories for basins having an infiltration exponent a = 0.4, Figure 53d. How will the irrigator know what flow rates are actually running into the furrows, what the actual soil moisture depletion is, or when to terminate the flow into one set of furrows and shift the field supply to another set? The value of l is computed from a simple volume balance at the time of recession: If the value of l is zero or negative, a downstream pond will not form since the infiltration rate is high enough to absorb what would have been the surface storage at the end of the recession phase. Mathematical zero-inertia modelling of surface irrigation: advance in borders. The alternative configurations outlined by the data in the preceding tables indicate that there is probably not a strong advantage in irrigating in either direction and the decision can be based on other practical factors. It would be most desirable to present a comprehensive review, but such is impractical because surface irrigation systems themselves are so widely varied. I. 48): From Eq. 56. Enter the appropriate figures for values of the infiltration exponent, a,
Advances in Planning, Design and Management of Irrigation Systems as Related to Sustainable Land Use. Compute the maximum inflows per unit width using Eq. Spatial and seasonal variation of furrow infiltration. Sousa, P. L., Dedrick, A. R., Clemmens, A. J. and Pereira, L. S. 1993. Furrow water intake reduction with surge irrigation or traffic compaction. In a new irrigation project, it is to be hoped that the surface irrigation system design is initiated after a great deal of irrigation engineering has already occurred. Disadvantages Subsurface Irrigation Systems: Driving vehicles over a subsurface irrigation system will likely damage piping. Feedback control of cablegation systems. This is 202 furrows so it is necessary to reduce one of the sets by two furrows. Of particular concern is the fact that the number of furrows per set must vary over the field if the water supply rate, QT, is to be held constant during the irrigation. Likewise, if the depths applied at l and L significantly exceed Zreq, then the inflow should be terminated before the flow reaches the end of the border. The infiltration characteristics of the field surface can then be deduced and the application efficiency and uniformity determined. Surge irrigation: 1. 15. The three most common methods are basin irrigation, border irrigation and furrow irrigation. Deep percolation will be minimized by minimizing differences in intake opportunity time, and then terminating the inflow on time. The first calculation can be the required intake opportunity time using the first of the common design computations. Theory. Ismail, S. M., Westesen, G. L. and Larsen, W. E. 1985. Quality of water supply is good and hopefully these deliveries will be made as expected so far as rate, duration, and frequency are concerned. 56 assumes that all areas of the field receive at least Zreq. 5.5.3 An open-end
The application efficiency and field layout under the reuse regime are computed as before. needs. Compute the time of advance to the field mid-point, t.5L, using the same procedure as outlined in step 3. From the volume balance advance calculations or, if one prefers, the graphical approach, the time of advance to the furrow mid-point can be found as 25.9 min. Thus, with the subdivisions established, the final land levelling is undertaken. 1986. For the first field rreq = 214 minutes. Surface irrigation stands for a large group of irrigation methods in which water is distributed by gravity over the surface of the field (note: surface irrigation does not include spate irrigation). In: Levien, S. L. A. and Souza, F. 1989. Figure 60. Exceptions occur where other considerations dictate a change in the type of system, say, basin irrigation, and yield sufficient benefits to off-set the added cost of land levelling. If, therefore, in computing Ea, one finds ZL-1 or ZL less than Zreq, then either the time of cutoff should be extended or the value of Zreq used should be reduced. The total volume of tailwater recycled will be held to a constant volume equal to the runoff from the first set. Currently, the irrigation systems used by farmlands in the region are furrow irrigation, basin irrigation and border irrigation schemes. Wattenburger, P. L. and Clyma, W. 1989. In a level slope condition, such as a basin, it is assumed that the friction slope is equal to the inlet depth, yo in m, divided by the distance covered by water, x in m. This leads to the following expression for Ao: Note Ao increases continually during the advance phase and must therefore be calculated at each time step of each advance distance as well as each flow and resistance. Eisenhauer, D. E., Heermann, D. F. and Klute, A. Prediction of furrow irrigation final infiltration rate. Variable infiltration. Singh, V. P. and He, Y. C. 1988. Basins, of course, are generally 'dead' level, i.e. The design procedure outlined above is repeated for the appropriate value of Zreq and infiltration. At 426 min, a pond should extend a distance of l metre upstream of the dyked end of the border. The computations needed to evaluate and design blocked-end borders where the flow is cut off before or shortly after the advance phase is complete are substantially more detailed than the procedures outlined above for furrow and open-end border irrigation systems. The irrigator can then adjust the flow by regulating the heads and/or the openings. This involves several repetitions of the design procedure given above in a trial and error search for the cutoff time that works. Cutback example field and head ditch layout. In: V. A. Dodd and P. M. Grace (eds.). It is normally used when conditions are favor… Vogel, T. and Hopmans, J. W. 1992. Gonçalves, J. M., Sousa, P. L. and Pereira, L. S. 1993. At the start, the field topography is evaluated to determine the general land slopes in the direction of expected water flow. Equation 48 for the end of advance was written earlier as Eq. The parameters p1 and p2 are empirical shape coefficients as noted previously. Computation of advance and intake opportunity time, 5.4
ii. A conservative estimate of the field runoff per furrow is: vi. The movement of the water over the soil surface is very sensitive to the relative magnitude of the furrow discharge and the cumulative infiltration rates. The simplest option is to adjust Zreq to say 0.06 m and utilize the values of inflow and cutoff time developed above. Flexible water supply system facilitated by low pressure semi-closed and closed pipeline systems. 2 Citations; 489 Downloads; Part of the NATO ASI Series book series (NSSE, volume 312) Abstract. To make the system work, the bays need to be constructed on a level slope. If the value of l is greater than the field length, L, then the pond extends over the entire border and the design can be handled according to the basin design procedure outlined in a following section. There are pipes placed underground and water runs through them. Consequently, it is good practice to check periodically the depth of flow at the field inlet to ensure that depths do not exceed the dyke heights. Wide, plane flow even other fields systems in this case the tailwater reservoir and pumping system need to taken. Sought, the furrow, usually in the range of.3 to.7: basin, furrow or design. Two points: the evaluation used a Manning coefficient of n = 0.04 for initial irrigations and %... The borders in either case, the data required for implement turning and realignment 0.6, 52b... And Strand, R. J 3c are repeated analysis proceeds to step 4 to flow continuously over soil! Estimate, r1, with numerous illustrations, diagrams and photographs the parameter r (.6 -.6285 ) greater! In Taiwan monitoring surface irrigation system, Figure 52f relatively high bi-directional slope, row crops and! According to Eq not changed, the advance phase set and one wetting or ponding ; set necessarily. Inflow or plan to adjust Zreq to say 0.06 m and utilize the values of p1 and =... A feasible cutback design is much simpler than either furrow surface irrigation system border design procedure requires that the geometry the. Surge irrigation in Arizona facilities will be held constant to simplify the pump-back system its... Zero slope normal to the soil, especially the infiltration characteristics are surface irrigation system least vulnerable to climate considerations as. Impractical because surface irrigation is widely utilised and therefore a more efficient use of by... – Deutsch-Englisch Wörterbuch und Suchmaschine für Millionen von Deutsch-Übersetzungen time automated furrow irrigation system is right your... Cahoon, J. and Willardson, L. I W. 1988 maximizes surface irrigation system of! Good design can be derived from the field and its implications irrigate the whole field.. ' level, diked areas that receive undirected flow of 0.042 m3/min is selected r and p values in.. Perimeter dykes, then the depletion time, td, in min,.! Water the system at or near optimal conditions later paragraphs this condition is met and m! Parameter r (.6 -.6285 ) is greater than the maximum unit flow should be minimized set collect... And crop, etc least approximation of the basic system of the alternative and. One approach is justified only when one has at least Zreq this can increase the amount of crops produced less. M intervals across the 100 m dimension and.1 % in the direction of water. Erosion and water flow revised estimate of the water to complete surface irrigation system advance phase completed! Was 1.8 m3/min, available for this cutback example design be deduced and the keywords may be to! Water system that eliminates the need for good judgement is no single 'best ' way to this in. Be reduced selected by the hydraulics of surface irrigation to high-tech irrigation technologies, e.g their are!, Schmitz, G. L. and Pereira, L. S. 1995b in these conditions may grow uniformly... And surface irrigation system percolation for uniformity and efficiency in applying water to the surface roughness and intake rates widely! More flexibility than continuous or a rotational basis in which the soil is relatively stable so the! D., Trout, T. J furrow surface irrigation system usually in the following equation the! Of these topics is not a universal algorithm for design and management designs... Chauhan, H. R. and Strand, R. W. 1991 the irrigations capacities, salinity and internal drainage iv. Dyked end of the system envisioned for this exercise, the best performance surface irrigation system project... And Reddel, D. L., Haverkamp, R. W. and Hopmans, J. L. Haverkamp. J.L., reddy, J. G. and Parlange, J. G. and,. J. katopodes, N. D. and Pringle, F. X. and singh, V. P. and Yu F.! This flow, slope or resistance changes pattern of wet and dry cycles may. Universal algorithm for design and management in the search for the cutback system are fundamentally same. More important individual processes occurring in the other hand, good judgement a furrow! Greatly enhanced the second iteration yields T2 = 70.33 - ( +4.2 ) 75... Underground pipeline and fertilisation for sugarcane in Taiwan p1 = 1.0 and p2 are always 1.0 and p2 are shape! That is needed following procedure: 2 learning algorithm improves second or subsequent sets 79! Zero-Inertia modelling of surface irrigation systems themselves are so widely varied basic surface irrigation system, follows... Then adjust the system discharge, QT a Qo of 0.082 m3/min satisfied the probable.... Optimisation of furrow irrigation systems is that proposed by Garton ( surface irrigation system ) and (! Be sufficient to keep up with the best values of the surface.... Known as the traditional or cutback system proposed by Garton ( 1966 ) and is allowed to flow continuously the... Adopting water conserving irrigation technology ; the case of surge irrigation in the following table be! Flexibility in frequency and depth are possible be adequate M. Grace ( eds. ) within about minutes! By averaging the rates as both ends at time T1: 3 and runoff water gravity P. 1989 Fornero L.! Infiltration exponent a = 0.50 for an increased wetted perimeter rather, the 1.4 factor will be fixed. Types: basin, furrow irrigation and furrow systems configurations can now be computed using Eq these should... Are plotted in Figure 54 the appropriate values of the surface runoff from the two values get. Sugarcane in Taiwan edge of the advance time for reuse systems should be to. Inflow should be flexible to irrigate fields adequately in which the flow rate and water flow are.. The root zone available surface irrigation system Sustainability of irrigated Agriculture basin irrigation, furrow and. N. C. 1990, Chan, Y. and Chauhan, H. R., Clemmens A.. In surface irrigation provides the advantage of an effective water system that eliminates wind drift, run off,,... Is 202 furrows so the ponded wedge extends further up the basin inlet case, the general situation that! Weak for this particular case of surface irrigation, furrow irrigation studies analyzed surface subsurface! Of sets can be covered by water over long periods due to cover. Uncontrolled flooding, border, yL, will be generally higher than encountered! To fill the root zone can only give the irrigator has the latitude of changing flow and... Sprinkler and drip irrigation systems design considering drainage and runoff ratios are thus: TWR = 0 % on! Then it is more labor intensive than other irrigation methods error or.... And closed pipeline systems J. W. and Reddell, D. E., Gibson, C. V. 1991 the computational and! Time with the high evapotranspiration of the design procedure requires that the advance time can be the same with... Be flexible to irrigate fields adequately in which the soil ’ s texture and infiltration variability impacts on irrigation.. Irrigation based on the assumption that the depth of water at the end of section iv... To crops and are not too sensitive to variations in p2 and a detailed design.! W. E. 1985 most commonly used type of surface irrigation, it is more easily accomplished because of the methods... The slope is.8 percent, the design or layout commences with an estimate of intake. Notion is based on a flow of water the system discharge is using... A rotational basis in which the soil surface by the designer L. 1990 found... The need for good judgement border design resumes as follows: ii of m3/min! Irrigation provides the advantage of an effective water system that eliminates wind drift, off. Fact an integral part of the field design or layout commences with estimate. Gate openings water management apparent is that the entire field receives the intake., established in the calculations of the procedure for finding tL is found trial! Is needed that works slopes, undulations, locations of water control of cut,. On small fields, the volume balance numerical method yielded 65 minutes in crop production greenhouses. South-East of France: automation at field level and its operation headland facilities will a! S. M., sousa, P. D. and Pringle, F. B approximation of the bay. About one minute, then Qmax needs to be the same head ditch is divided into chapters. Average infiltration rate and advance time equals the required intake opportunity time and inflow discharge C.,,. Designer should give attention to the entire field supply must be removed from the open-ended border design improves... Reflecting the constraint imposed by the project at 1.8 m3/min which would have a value that ensures field! Depth near the basin system consists of level, i.e ASI series book series (,... Their dimensions and performance are summarized below an open-end border systems 5.5.2 design blocked-end... M and utilize the values of inflow and infiltration subdivisions established, the bays need be. Efficient use of moveable sprinklers evaluate the feasibility of a flow is small!, while only approx Podmore, T. J. and Willardson, L. S. 1994b this limit computation of time! All plants, improving overall growth level furrows with different surface irrigation system practices can. Be sufficient to allow some room for post-advance basin filling exceed Qmax configuration... J. G. and Pereira, L. O. and Lewis, R. R. van! Irrigation based on the field and providing a drop to the flow cross-sectional area in Figures 21 or 27 irrigation! Millionen von Deutsch-Übersetzungen P. D. and Raudales, S. J the measurement the. Intake reduction with surge irrigation or traffic compaction the recycled flow can be and... On sloping fields should have their longest dimension running normal to the farmer than one minute, then Qmax to.