Interactive property sketch · no address required

Plan yard drainage before you dig.

Map wet spots, downspouts and candidate outlets, then use your own dimensions to estimate runoff, check route fall and compare practical drainage approaches before you buy materials.

Build my drainage sketch Diagnose my wet-yard problem

Private by defaultYour plan stays in this browser unless you copy a share link.

Storm what-ifCompare 0.5, 1, 2 or 3 inch storms—or enter your own.

Route + grade checkScale each route, then add measured fall to see its end-to-end grade.

Turn a wet-yard problem into measurements

Start with the water source and outlet, then carry the same plan through runoff, route length, measured fall and mitigation checks.

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Storm volume

Estimate roof, pavement and lawn runoff for a chosen rainfall depth with assumptions kept visible.

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Property sketch

Move wet spots, downspouts and one or more outlets on a scaled planning grid and compare route length.

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Screen approaches

Compare surface grading, swales, collection drains, infiltration storage and rain-garden concepts against the sketch.

A better sequence

Follow the water from source to overflow

Most drainage mistakes happen when one link is skipped: a product is chosen before the source is understood, a route is drawn before elevation is measured, or storage is sized without an overflow plan.

Four-step yard drainage workflow showing source, route, outlet and overflow

Wrivel keeps these four questions together so a drainage idea can be checked before materials are bought.

1Find the source

Roof, hardscape, slope, seepage or several sources at once.

2Measure the route

Distance and actual fall matter more than how the yard looks by eye.

3Verify the outlet

Lower is not enough; the endpoint also needs to be lawful and stable.

4Plan overflow

Every basin, barrel, dry well or pipe route can be exceeded or blocked.

Yard water-flow planner

Build a first-pass drainage plan

Use measured dimensions when you have them. The sketch is for early decisions before a contractor, landscaper or engineer verifies grades, soil, buried utilities, setbacks, discharge rights and local code.

2. Sketch the water problem

Drag markers, or Tab to a marker and use arrow keys. Each source routes to its nearest marked outlet. Sketch shapes are visual; numeric roof/driveway/hardscape areas come from the fields in step 1.

wetoutletdownspout

High/low markers are visual notes only. Wrivel does not infer terrain from them; verify elevations with a level, laser or survey where consequences matter.

3. What this storm produces

Total estimated runoff—

Roof runoff—

Impervious share—

Combined route estimate—

Example gravel-trench voids—

Lawn runoff scenario—

Planned route breakdown + measured fall

Each wet spot or downspout is paired with its nearest marked outlet. Add the measured vertical fall for a route to calculate its end-to-end grade. Distances are straight-line planning estimates from the scaled sketch, not trench takeoffs; verify intermediate grade breaks in the field.

Storm ladder for this property

Same property and surface assumptions, four rainfall depths. This is volume sensitivity, not a peak-flow or pipe-capacity calculation.

4. Test a mitigation what-if

Model two explicit changes without pretending they are a full drainage design: send part of roof runoff to a verified safe outlet, and temporarily capture some of the remaining roof runoff in storage.

Roof runoff redirected to verified outlet (%)This changes the water left to manage on-site; it does not make the water disappear.

Empty roof-fed storage at storm start (gal)Barrel, cistern, basin or verified storage volume. No infiltration during the storm is assumed here.

Baseline runoff—

Redirected to outlet—

Temporarily captured—

Still to manage on-site—

Roof overflow after diversion + storage: —. Storage is treated as empty at the start of each event and available only to roof runoff after the redirected share.

Approaches worth screening

5. Field verification + project brief

Mark only checks you have actually confirmed. Wrivel then turns this plan into a concise handoff for a site visit, contractor quote or your own next measurement round.

Route elevations / grade breaks measured Outlet location and discharge permission verified Buried utilities / locate requirements checked Boundaries, septic, wells and sensitive features checked Overflow path identified for a larger storm

0 of 5 field checks markedMeasure at least one route fall and verify the outlet before treating the sketch as a field-ready concept.

Before digging: locate buried utilities, verify where discharge is lawful, keep water away from foundations and neighboring property, and confirm soil/infiltration and elevations on site.

Privacy: the working plan is saved in this browser using local storage. A share link encodes the planner inputs and sketch coordinates in the URL; anyone with that URL can read those values. Planner data details.

Choose the next calculation only when you need it

Soil infiltration test

Replace a soil guess with repeated drain-down measurements from the actual location you may use for infiltration.

French drain vs swale

Use a quick route screen for surface water, shallow seepage, outlet availability and usable width.

Dry well storage

Turn a roof catchment and storm into target capture volume and gross stone-zone volume.

Grade calculator

Convert measured run and drop into percent slope before assuming gravity will work.

Rain garden vs dry well

Compare visible surface storage with underground infiltration only after soil and overflow checks.

12-step field checklist

Use a printable source-to-overflow checklist before digging or requesting quotes.

Start with the symptom

What kind of yard drainage problem are you actually seeing?

Use the symptom page first when you do not yet know whether the real issue is surface runoff, roof discharge, a point low spot or subsurface wetness.

Standing water

Water pooling after rain

Use location, drain-down time, visible inflow and outlet availability to decide what deserves measurement first.

Roof runoff

Downspout drainage

Calculate the storm volume reaching one downspout and the end-to-end grade to a candidate outlet.

Hardware choice

Catch basin vs French drain

Match point surface collection against linear subsurface collection before committing to a trench.

Roof storage

Rain barrel size

Compare estimated roof runoff with barrel or cistern capacity and see captured water versus overflow.

Common drainage questions, answered with the next measurement

Why does my yard hold water after rain?Separate visible inflow from water that appears in place; then note how long it persists and whether a lower outlet exists.

Should I install a French drain?Only after you know the source, route and outlet. Surface runoff may be better screened against grading or a swale; a discrete low point may fit a catch basin.

How much water comes off my roof?Use horizontal contributing roof area and rainfall depth. A 55-gallon barrel can fill much faster than the roof area suggests by eye.

Can I bury a downspout line?First measure route length and fall. End-to-end grade is useful, but you still need continuous fall, a safe outlet, utility clearance and local compliance.

From plan to maintenance

Use Wrivel before digging—and when a system stops working

A useful drainage site should cover more than the first design idea. These tools continue the workflow into field preparation, material quantity and troubleshooting.