Irrigation System Design

What the design is

The design is not a drawing with pipes on it — it's a document that specifies the system line by line, from the source's measurement to the emitter's flow. The design service page has the service's scope; this guide is the method, so the farm's owner can read the document, ask the right questions, and know what the numbers mean. The choosing guide is the sequence that feeds the design; this guide is the design's own method.

The design's parts, in the order they're set

1. The water strategy. The source's assessment — the water quality & quantity guide's four questions: the dry-season yield, the quality (the filtration spec), the position (the gravity or the pump), the storage (the gap's carrier). The water strategy is the design's foundation — the number the rest is built on.
2. The zone structure. The blocks and the zones, drawn from the crop plan. The zone's count is set by the pump's practical run time — the calculation is how long the pump must run to water the whole field, and whether that's a working day or a three-day job. The zone map is the design's skeleton, and the block map (the as-built's foundation) is where the zones sit on the ground.
3. The hydraulic calculation. The pipe sizes from the flow and the distance, the pressure at the farthest zone, the friction budget. The mainline is sized for the total flow; the laterals are sized for each zone's flow; the pressure at the far end is checked against the line's working range. The undersized mainline is the design's classic shortcut — the field that's always a little dry at the end — and the calculation is the prevention.
4. The crop specification. The drip line or the tape, the emitter spacing and the flow, from the crop's spacing and demand. The crop pages have the per-crop specs; the tape vs line guide is the economics. The line spec is the design's crop-side, and it's set from the actual planting, not the crop's type.
5. The head assembly. The filtration (matched to the source's quality), the valves (per zone), the gauges (the pressure's read), the regulator (where the pressure is higher than the lines want), and the fertigation injection point (where the feed is in the plan, after the filter). The head is the design's first section, and it's where the system is either alive or leaking.
6. The pump specification. The flow and the head from the calculation — the litres per hour the field needs, plus the metres the water must rise. The power option (the diesel, the electric, the solar) is the farm's economics, and the pump page has the component's range. The pump is specified from the calculation, not the label.
7. The automation scope. The timer, the controller, the solenoids, the sensors — specified at the level the operation earns. The automation guide walks the levels; the automation is the design's labour side.
8. The irrigation schedule. The starting run time and the frequency, per zone, from the crop's stage and the soil's character. The drip guide walks the method; the schedule is the design's crop-side, refined through the season.
9. The as-built and the expansion plan. The map, the zone table, the material schedule, and the routes for the blocks the farm will add later. The as-built is the design's document that the maintenance runs from, and the expansion plan is the design's future — the mainline routed for the full farm, the head sized for the growth.

The hydraulic calculation — the numbers, honestly

The calculation is the design's core, and the honest read is the logic, not the arithmetic (the arithmetic is the engineer's job, and the design service is where it's done):

• The flow. The total flow is the sum of the zones' flows — each zone's flow is the line's flow (the emitter flow × the emitter count per line × the line count), and the mainline carries the total. The flow is the number the pipe is sized for.
• The pressure. The pressure at the farthest point is the check — the source's pressure (the gravity's head, the pump's head) minus the friction (the pipe's length, the flow, the fittings) minus the elevation (the field's rise). The result must be in the line's working range (the ~1 bar the standard drip line wants) — the how drip works guide walks the pressure's logic.
• The zone's run time. The run time is the crop's daily need divided by the zone's flow — the hours the zone runs per day to meet the crop's demand. The run time is the pump's practical constraint, and the zone's count is set from it (the choosing guide's scale step).

The calculation is where the design's honesty lives — the pipe that's sized for the flow, the pump that's specified for the lift, the zone that's counted for the run time. The kit chosen against the budget skips the calculation, and the field shows the skip in the first season. The assessment is the visit where the farm's measurements feed the calculation; the design is the document that holds the numbers.

The as-built — the document that makes the system work

The as-built is the design's output that the farm keeps — the map (the zones, the mainline route, the head's position), the zone table (the valve, the line spec, the schedule per zone), the material schedule (the components, the quantities, the specs). The as-built is what the maintenance runs from, what the repair finds the fault against, and what the upgrade builds on. The install without the as-built is the system that's a mystery in the second season — the install page has the handover's standard, and the as-built is the document that makes the handover real.

The design's honest lines

• The design is the method applied to the farm's measurements — the choosing sequence is the input, the water assessment is the constraint, the crop's demand is the number. The design is not a template; it's the farm's system, specified from the farm's numbers.
• The design is the document, not the drawing — the map is the picture, the specification is the content. The farm's owner reads the specification (the line spec, the zone table, the schedule), and the design service is where it's written.
• The design is the expansion plan — the mainline routed for the full farm, the head sized for the growth, the routes for the blocks the farm will add. The design that plans the growth is the design that pays for itself in the second block.
• The design is the maintenance's foundation — the as-built is the calendar's map, the zone table is the routine's reference. The maintenance service runs from the as-built, and the maintenance guide is the routine the as-built holds.

What a good design looks like

The farm's own measurements (the assessment's visit), the water strategy (the source's four numbers), the zone structure (the block map, the zone's count from the run time), the hydraulic calculation (the pipe sizes, the pressure's check, the run time), the crop specification (the line, the emitter, the lines per bed or tree), the head assembly (the filtration, the valves, the gauges, the regulator, the fertigation point), the pump specification (the flow and the head, the power option), the automation scope (the timer, the controller, the solenoids, the sensors), the schedule (the run time and the frequency, per zone), and the as-built (the map, the zone table, the material schedule, the expansion plan). The design service is the document, and the quote is the document with a price. The cost guide has the indicative ranges, built from the design's lines.