Two 80-acre pattern-tile jobs. Same county, same soil, same crew. One makes you 22 percent. The other makes you 4 percent. The difference is not your crew, your plow, or your pipe supplier. It is that one field sat a quarter mile from a legal outlet and needed 60-foot spacing, while the other sat two miles out with tight soils that demanded 30-foot centers. You bid both at the same per-acre price, so the second job installed nearly twice the footage — plus a deep main cut through a ridge — for the same revenue.
That is the central bookkeeping discipline of the drainage business: the acre is a sales unit, but the foot is the cost unit. Every contractor who survives long enough learns to bid, track, and review every job in dollars per installed foot, with the outlet priced as its own line item. Here is how to run that system, from the estimate sheet to the year-end tax conversation that fills your fall schedule.
Why per-acre bidding quietly destroys margin
Pattern tiling a field means laying parallel lateral lines at a designed spacing, all feeding a larger main that carries water to an outlet — a ditch, stream, or district tile. The footage per acre is pure arithmetic: one acre holds 43,560 square feet, so 60-foot spacing needs about 726 feet of lateral per acre, while 30-foot spacing needs about 1,452 feet. Same acreage, double the pipe, double the plow time, double the fuel and wear.
Spacing is not your choice to make freely. It follows the soil. Open, permeable soils drain fine on 60- to 80-foot centers, which is the standard pattern-tile range across much of the Corn Belt. Tight, heavy soils need narrower spacing — down to 30 feet — and shallower placement, because tile draws the water table down in a wide flattened V and shallow tile simply reaches less ground sideways. Industry veterans put typical parallel-drain layouts at 50 to 100 feet apart depending on soil, with closer spacing always costing more per acre for exactly the footage reason above.
The going installed price for pattern tile runs roughly $1,000 to $1,500 per acre in the Midwest, with some contractors reporting most jobs landing near $1,500 and a wider range of $1,200 to $2,000 depending on conditions. Roughly half of that is pipe and materials and half is labor and installation. That 50-50 split is your first bookkeeping checkpoint: if a job's material share drifts far above half, either pipe prices moved after you bid or the footage estimate was wrong. Both are fixable, but only if you track pipe and installation separately instead of lumping everything into one per-acre cost.
Practical fix: keep the per-acre number on the quote the farmer sees — it is the language landowners think in — but build it bottom-up from a per-foot cost every time. Footage from the design (laterals plus main), times your installed cost per foot, plus the outlet allowance, divided by acres. When spacing tightens from 60 to 30 feet, the per-acre price should nearly double. If your quote template cannot do that math automatically, that is the first spreadsheet to fix this winter.
The outlet moves your cost more than spacing does
Spacing changes footage predictably. The outlet changes everything unpredictably, which is why experienced estimators price it separately. Cost depends in large part on how close the farm is to an outlet, and the reasons compound:
- Main size and depth. Laterals typically run around 30 inches deep in 3- or 4-inch pipe. Mains that must cut through a ridge to reach an outlet can run several feet deep in large-diameter pipe, and deep excavation is slower, thirstier for horsepower, and harder on shanks and boots.
- Distance. Every extra thousand feet of main is footage with a worse margin profile than laterals — bigger pipe, deeper cut, more restoration — and it serves zero additional billable acres.
- Crossings and permissions. Getting to the outlet can mean road crossings, neighbor easements, or tying into a drainage district system, each with its own permit, fee, and schedule risk.
- Future capacity. Good designs oversize the main so the farmer can add laterals later. That is the right engineering call, but it front-loads pipe cost into this year's job and must be in the bid, not absorbed.
The bookkeeping move is to make the outlet its own cost code on every job: lateral footage, main footage by diameter, outlet works (crossings, structures, restoration), and design/survey. When a job underperforms, this split tells you within minutes whether the miss was a spacing/footage error, an outlet surprise, or a productivity problem. Contractors who book everything to one "job cost" account learn nothing from their losses.
Pipe is half your cost, so treat it like inventory
With materials running about half of installed cost, pipe purchasing is a profit center disguised as procurement. Three practices separate organized operations:
Buy ahead of the season. Demand for corrugated HDPE pipe routinely outruns manufacturing capacity in strong farm-income years, and contractors who take delivery of fall pipe in spring are the ones still installing in November while competitors wait on resin. Booking pipe early is also a price hedge — plastic pricing follows petroleum and post-disruption surges have bitten bidders who priced fall jobs off spring pipe quotes.
Put escalation language in every quote. A per-acre price that is firm for 90 days while pipe floats is a margin trap. Either hold the quote for 30 days, or state that pipe is billed at installed cost plus a handling percentage. Farmers understand this — they watch input prices themselves.
Track waste per job. Fittings, stubs, damaged sticks, and over-ordered coils add up. A simple metric — pipe purchased versus footage installed — catches both theft and sloppy handling. Anything over a few percent waste deserves a conversation with the crew lead.
One accounting nuance worth knowing: pipe sitting in your yard is your inventory, and pipe sitting on the customer's farm before installation is not yet a depreciable improvement for them. That distinction drives the year-end tax conversation below, and it means your December delivery receipts should clearly show what is installed and working versus merely delivered.
The equipment math: plows, GPS, and the depreciation that pays for them
A drainage contractor's balance sheet is dominated by iron. A new pull-type tile plow with GPS arm runs in the mid-$40,000s, while large hydraulic and self-propelled machines run from roughly $95,000 to $185,000 depending on specification — before the tractor, the GPS autosteer and grade-control system, the stringer trailers, and the support trucks. Laser or GPS grade control is not optional at these prices; holding grade to a fraction of a percent over a quarter-mile run is what separates a system that drains for a century from a lawsuit.
That capital intensity is exactly why the tax code is your friend. Tile plows and guidance systems qualify for Section 179 expensing and bonus depreciation, which means a profitable year can fund next year's capacity with pre-tax dollars. The strategic pattern most contractors follow: take deposits and progress payments through the fall rush, true up the year's profit in early December, and time equipment purchases so the deduction lands in the high-income year.
Track equipment at the machine level, not as one "equipment" blob. Each plow should carry its own record of purchase price, Section 179 taken, repair costs, feet installed, and revenue generated. That file answers the only equipment question that matters — what does this machine cost me per installed foot — and it tells you when a repair bill exceeds the remaining value of an old plow versus financing its replacement.
Seasonal cash flow: the weather owns your schedule
Prime installation season runs from harvest until soils freeze, with a growing shoulder of spring and summer work as demand has stretched the calendar. But the work remains weather-dependent in a way that should terrify anyone running on thin cash: a bad stretch between Thanksgiving and Christmas can erase two months of tiling, and with it the revenue you planned to collect before year-end.
Contractors manage this four ways:
- Deposits that commit the schedule. A meaningful deposit at booking — enough to cover the pipe order — filters serious jobs from wish lists and funds the inventory sitting in your yard.
- Progress billing tied to footage. Bill lateral footage as installed, not one lump sum at completion. Your costs accrue by the foot; your invoices should too.
- A backlog you can see. The healthiest contractors carry a booked schedule into next fall and communicate weather risk explicitly: customers who know December work is weather-contingent do not panic when the ground freezes early.
- A spring expense plan. Insurance, loan payments, and shop payroll do not pause when the plows do. Hold back a reserve from fall collections rather than spending the season's profit on equipment before spring cash needs are covered.
Mechanic's lien basics belong in this section too. Drainage work improves real estate, which generally supports lien rights if a landowner does not pay — but deadlines and notice requirements are state-specific and unforgiving. Know your state's private-work lien deadline before you need it, not after.
The year-end tax talk that fills your fall calendar
Here is the conversation that books work: farmers with profitable years want deductions before December 31, and drainage tile is one of the most attractive places to put that money. Improved drainage can lift corn yields by 10 bushels per acre or more and soybeans by around 4 bushels in long-running trials, with much larger responses on poorly drained ground — and tile systems last 70 to 100 years, so the investment outlives the loan by generations. Land appraisers have measured value gaps of up to 20 percent — as much as $2,000 per acre — between poorly drained farms and tiled ones, which means a $1,000-per-acre tile job can pay for itself in land value alone before a single extra bushel.
But the tax benefit has a tripwire your customers need to hear from you, and it directly affects your scheduling and billing. A drainage project must be completed and in use — or ready to use — for the farmer to depreciate it. Pipe delivered but not installed is inventory, not an improvement. On a $200,000 project that is half done at year-end, the farmer can only write off the completed half, and should pay you for that completed half before the cutoff.
Turn that rule into process:
- Schedule year-end-motivated jobs early in the fall window, with a written completion target and an explicit weather caveat.
- Invoice completed phases separately in December, with as-installed footage and a completion statement the farmer's CPA can rely on.
- Document partial completion precisely. A tile map showing which laterals are in the ground and functional is worth more to the customer than a handshake promise to finish in spring.
Farmers may also expense qualifying soil and water conservation work under tax code Section 175, subject to an annual cap of 25 percent of gross farm income with the excess carried forward — another reason the completed-and-paid paperwork matters. You are not their CPA, and should say so, but being the contractor who hands them clean December documentation is a competitive advantage that costs you nothing.
Five numbers to review every month
You do not need a CFO. You need five numbers, reviewed monthly, computed per job and in total:
- Revenue per installed foot. Total billings divided by total footage installed. This is your real price. Watch it drift down and you are discounting without deciding to.
- Gross margin per foot. Revenue per foot minus direct cost per foot (pipe, fittings, fuel, crew labor, equipment cost per foot). Bid target and actual, side by side, for every closed job.
- Pipe waste percentage. Pipe purchased versus footage installed. The canary in the coal mine for handling, estimating, and shrinkage problems.
- Machine utilization days. Billable install days per plow per month versus available weather days. Low utilization with a full backlog means mobilization and logistics are eating the season.
- Days sales outstanding. Drainage invoices should not age like wine. Anything past 45 days needs a phone call, because spring work for slow payers is how receivables become write-offs.
Run these from November through March and you will know, before the next season starts, which job types to chase, which to reprice, and which crew and machine combinations actually made money.
Keep Your Field Records as Clean as Your Grade
Drainage contracting rewards the operator who measures. Per-foot bidding protects margin when spacing tightens, a separate outlet allowance absorbs the deepest surprises, machine-level records turn iron into a known cost per foot, and December documentation turns tax law into booked work. The contractors booked solid into next fall are not lucky — they are the ones whose numbers told them which jobs to take.
The same discipline applies to the business behind the plow. As your footage grows, maintaining clear financial records is what lets those five monthly numbers come from your books instead of your gut. Beancount.io provides plain-text accounting that gives you complete transparency and control over your financial data — no black boxes, no vendor lock-in. Get started for free and see why developers and finance professionals are switching to plain-text accounting.
