Soil and Water Management: 7 Practices With Costs

Soil and water management means keeping soil able to take in, store and release water, then giving crops only the water they can use. In agriculture, seven practices do most of the work: soil testing, cover crops, reduced tillage, crop rotation, measured irrigation, drainage with salinity and erosion control, and rainwater harvesting. The stakes are large. Agriculture accounts for 69 percent of water withdrawals worldwide (FAO AQUASTAT), and the US EPA names soil erosion and nutrient loss from farmland among the leading causes of water quality problems in the United States.

This guide is for farm owners and managers deciding where the next dollar and the next week of labour should go. Each practice below says what it does, what evidence supports it, what it can cost and when it may not pay. Costs use one dated public list so you can compare practices on the same basis, and the calculator lets you test your own irrigation numbers.

The 7 soil and water management practices compared

The order below follows a sensible sequence: measure first, protect the soil next, then fine-tune water. It is a working order and not a ranking by profit, because the best first step depends on the field. Listed amounts come from the Pennsylvania NRCS cost list for fiscal year 2026, used by the USDA conservation programmes EQIP and CSP. They are one state’s programme figures, not contractor quotes.

How we chose these practices

We kept practices that directly change how soil holds water or how water moves across and through a field, and that have public guidance or research behind them. Pest control and farm labour planning, which the older version of this page covered, matter to a farm but are separate topics, so only the soil and water links remain here.

Practice 1: Test the soil and plan nutrients

A soil test tells you pH, nutrient levels and, if you ask, salinity and organic matter. It is the base for every later decision. The EPA lists targeting fertilizer and manure through soil testing, crop-specific calibration and careful timing as ways to raise uptake and cut runoff.

• Do this: sample each management zone separately. A field with a sandy ridge and a clay hollow should not share one average result.
• Add a texture check: texture sets how fast water enters and how much the soil can hold.
• Keep records: compare the same zones at the same time of year, so that season does not hide or fake a trend.

Soil type also limits how fast you can apply water. FAO gives these basic infiltration rates: sand under 30 mm per hour, sandy loam 20 to 30, loam 10 to 20, clay loam 5 to 10 and clay 1 to 5. Water applied faster than the soil can absorb it will pond or run off, so a sprinkler rate that suits loam may be wrong on clay.

▶ How soil and water shape crop production · 9:40

Practice 2: Grow cover crops on bare ground

A cover crop is planted mainly to protect and feed the soil rather than for sale. Roots hold soil in place, residue shields the surface, and legumes such as clover and hairy vetch fix nitrogen. The EPA notes that cover crops can take up leftover nutrients that might otherwise leave the field.

Chart

What surveyed farmers paid for cover crop seed

Share of respondents by price per acre, %, selected bands

Chart

Reported cover crop yield gain: drought vs wet year

Average yield gain reported by surveyed US farmers, %

The evidence on organic matter is positive but gradual. SARE reports that results pooled from many experiments showed organic matter rising 8.5% above original levels and soil nitrogen rising 12.8%. Longer growth and less tillage gave larger gains.

On yield, SARE’s national farmer survey series reported higher average yields with cover crops in every year it ran, with the largest gains in the 2012 drought. These are farmer-reported results rather than controlled trials, so treat them as a guide.

Seed is the first bill. In the 2019–2020 survey of 1,172 farmers, the most common seed price band was $11–$15 per acre, and about one-fourth paid $26 or more (SARE). Add planting and termination, and check that the cover crop will not use spring moisture your cash crop needs in a dry year.

Practice 3: Reduce tillage and keep residue on the surface

Leaving soil undisturbed from harvest to planting, with residue on top, reduces runoff (EPA). No-till means planting directly into the previous crop’s residue. Strip-till disturbs only narrow planting rows.

Yield is where honest advice matters. A global meta-analysis in Nature of 5,463 paired yield comparisons from 610 studies found that no-till alone reduces yields overall, though results vary. The penalty shrank when no-till was combined with residue retention and rotation, and that full package raised rainfed yields in dry climates.

So do not judge no-till as a single swap. It is usually strongest as part of a system, especially on dry or erosion-prone land. Adoption also needs patience: a study in Choices magazine reports that US cover crop and no-till area grew by 5.0 and 7.9 million acres between 2012 and 2017, and that some counties lost area under these practices in that period. Test on a representative field before changing the whole farm.

▶ Why organic matter matters in soil · 7:33

Practice 4: Rotate crops to protect soil and income

Rotation means growing different crops in sequence on the same field. SARE says yields in rotations are typically 10% higher than monoculture in normal seasons and as much as 25% higher in droughty ones. It also links rotation with fewer problems from insects, nematodes, weeds and plant diseases, plus more varied income.

• Vary root depth: deep and shallow roots draw water and nutrients from different layers.
• Add a legume: it supplies some nitrogen for the next crop.
• Use nonhost crops: SARE gives corn rootworm and soybean cyst nematode as examples of pests that rotations with nonhost plants can control.
• Check the market first: a rotation only works if you can sell, store or feed each crop.

Practice 5: Measure irrigation water and apply it efficiently

Among water management practices, measuring demand comes before buying new hardware. FAO’s crop coefficient method calculates crop water use as ETc = Kc x ETo. ETo is reference evapotranspiration, the water a standard grass surface would lose in your weather. Kc is a crop coefficient. FAO’s mid-season values include 1.20 for field corn and 1.15–1.20 for cotton.

Chart

Indicative field application efficiency by method

Share of applied water used effectively, %

Then allow for losses. FAO’s indicative field application efficiency is 60% for surface irrigation, 75% for sprinklers and 90% for drip, and it warns that poor discipline can lower them. Those figures describe how much applied water reaches effective use on the field, before any canal losses.

The shift to pressurized systems is well under way. USDA ERS reports that pressurized irrigation in the western United States grew from 14.7 million acres, or 37 percent of irrigated cropland, in 1984 to 29 million acres, or 74 percent, in 2023. ERS also reports 54.9 million irrigated acres nationwide in the 2022 Census of Agriculture, with California and Nebraska the two largest states.

A better system does not always mean less water drawn from a river or aquifer. If saved water is used to irrigate more land, total use may not fall. Check your water right, allocation and local groundwater rules before planning around the savings.

Scheduling can begin cheaply: track weather-based ETo, check soil moisture in the root zone, and record each irrigation. Our alfalfa irrigation scheduling case study and almond orchard irrigation plan show the idea in two dry climates.

Practice 6: Control drainage, salinity and erosion

These three problems often sit on the same land, and each moves water or soil to the wrong place.

Chart

Soil salinity selected crops tolerate with no yield loss

ECe at 100% yield potential, dS/m, selected crops

Drainage

Drains remove water that stays in the root zone too long, but they can also carry nutrients out quickly. The EPA lists tailored drainage methods among the ways to address nutrient runoff. Control structures can hold water back at times when the field does not need to drain. Check local permit rules and any downstream obligations before altering a drain.

Salinity

Salts left behind by irrigation water can cut yield even when the soil looks wet. Salinity is measured as electrical conductivity in decisiemens per metre (dS/m). FAO’s water quality guidelines give the soil salinity (ECe) each crop tolerates with no yield loss. Barley tolerates 8.0 dS/m and bean only 1.0, so crop choice is itself a salinity tool.

Extra water can leach salts below the roots. FAO’s leaching requirement equation is LR = ECw / (5 x ECe – ECw), where ECw is irrigation water salinity. For water at 1.0 dS/m and a crop limit of 6.0, that gives about 0.034, so about 3.4% of the applied water should pass below the roots. Leaching only works if the field drains, which is why salinity and drainage belong together.

Erosion

Filter strips, grassed waterways and windbreaks slow water or wind before soil leaves. Vegetated buffers around fields and streams intercept runoff (EPA). Iowa State University’s STRIPS research reports that converting 10% of a crop field to diverse native perennial vegetation cut sediment movement off the field by 95%, with total phosphorus and nitrogen in runoff down by 90% and 85%. Those results come from specific Midwest trials, so expect different numbers on other soils and slopes. Land in a strip also leaves production, which is why the Pennsylvania list includes foregone income in its filter strip scenario.

Practice 7: Harvest and store rainwater

Rainwater harvesting collects runoff from roofs, roads or slopes for later use, or holds rain where it falls. Contour bunds are low earth banks built along the slope. Swales are shallow ditches on the contour. Both give water more time to soak in.

The sizing sum is simple: 1 mm of rain on 1 square metre equals 1 litre. So 500 mm of rain on a 2,000 square metre roof yields 1,000 cubic metres before losses. Multiply by a runoff share you have measured or estimated for that surface, since roofs shed more than soil. Compare the result with the seasonal need from the calculator in Practice 5 to see how much of a dry spell storage could really cover.

Before you build, check three things: whether local water law allows you to capture runoff, whether the dam or pond needs an engineering design or a permit, and how much storage will evaporate or seep away. Rules differ widely between places.

What soil and water management costs and how to pay for it

Use the listed amounts as a scale for comparison. Annual management practices such as rotation, no-till and cover crops are listed per acre, with annual payment caps. Structures such as waterways and ponds are larger one-time jobs that need upkeep. Your real cost depends on soil, slope, machinery, labour and contractor rates, so get local quotes.

In the United States, EQIP and CSP are the main federal programmes to ask about; your local USDA service center can explain current eligibility and rates. Elsewhere, ask the national agriculture ministry or your extension service. Pennsylvania’s list applied to fiscal year 2026 contracts, so ask for the current version.

A five-step plan for your farm

1. Diagnose: collect soil tests, water source and water quality results, yield records and photos of problem spots after heavy rain.
2. Choose two changes: pick the problems costing the most. A wet hollow needs a different fix from a salty corner.
3. Run a side-by-side trial: keep a comparison strip with your old method on the same soil.
4. Measure simple numbers: yield, water applied, fertilizer used and input cost per acre or hectare.
5. Expand slowly: give soil practices more than one season, since organic matter moves slowly and one year’s weather can mislead.

Infographic

Soil and water plan in 5 steps

1. 1DiagnoseCollect soil, water and yield records.
2. 2Choose twoPick the costliest problems.
3. 3TrialKeep a comparison strip.
4. 4MeasureTrack yield, water and cost.
5. 5ExpandScale up after more than one season.

Satellite vegetation maps can help you decide where to walk first by showing which parts of a field are falling behind. They show the change in the crop, not its cause, so confirm with a soil probe or test. Farmonaut offers this kind of satellite field monitoring.

Common barriers and practical fixes

• Upfront cost: begin with low-cost steps such as testing, scheduling and rotation, and ask about cost-share before buying equipment.
• Knowledge gaps: extension services and farmer groups can share local trial results, which matter more than national averages.
• Yield worries during change: trial on part of the farm. The Nature analysis shows why no-till alone may cost yield at first.
• Dropping out: the Choices article shows that many counties lost area under these practices, which suggests that some farmers stop. Budget for a few seasons and adjust the method before abandoning it.

This guide covers cropland. Mine sites and rehabilitation follow separate water and soil rules. For that work, see open pit mining’s environmental effects and our satellite-based mineral detection page, use the mining query form, or contact us.

▶ Seven simple ways to protect soil and water on a farm · 4:34

Frequently asked questions

What is soil and water management in agriculture?

It is the set of field decisions that keep soil productive and use water carefully, including testing, soil cover, tillage, rotation, irrigation, drainage and water storage. The aim is steady yields with less waste and less runoff.

What are the best water management practices for farms?

Start by estimating crop demand with ETc = Kc x ETo, checking soil moisture and recording what you apply. Then consider system upgrades. FAO’s indicative application efficiency is 60% for surface, 75% for sprinkler and 90% for drip irrigation.

Which soil management practice should I start with?

A soil test, because it shows whether the limit is pH, nutrients, salinity or texture. On land that sits bare between crops, cover crops are often a sensible next trial.

Does drip irrigation always save water?

It applies water more precisely on the field, but total use may not fall if the saved water irrigates extra land. Filter maintenance and good scheduling also decide the result.

Does no-till increase yield?

Not on its own, according to the 610-study Nature analysis, which found lower yields overall. Combined with residue retention and rotation, the yield penalty shrank, and rainfed crops in dry climates gained.

How much do cover crops cost per acre?

In SARE’s 2019–2020 survey, seed for most respondents cost between $6 and $25 per acre, with about one-fourth paying $26 or more. Planting and termination are extra.

How do I know if my soil is too salty?

Have a lab measure ECe and compare it with FAO’s crop tolerance values, such as 1.7 dS/m for corn and 6.0 for wheat. White crusts and patchy stands are clues, not proof.

How much water does an acre or hectare of crops need?

It depends on local ETo, crop stage and rainfall. One millimetre over one hectare is 10 cubic metres, and the calculator on this page converts your numbers into a seasonal volume.

How can technology help with water management in agriculture?

Soil moisture sensors, weather-based scheduling and satellite crop maps all help you see where and when to act. They support decisions but do not replace field checks.

How long until soil health practices show results?

Runoff and ground cover can change within a season, but organic matter moves slowly. The California clover experiment SARE describes ran for five years. Measure over several seasons.