A beautiful inground pool deserves a dry, stable backyard. Poor drainage creates puddles, slippery decks, heaving concrete, and hydrostatic pressure that can stress your pool shell and equipment. If you’ve been searching for pool drainage around pool, this guide walks you through the essentials: how to move water away from the pool efficiently using deck pitch, French drains, and sump systems—plus smart yard grading and downspout control.
Why Pool Drainage Matters
- Safety: Standing water = slips and algae.
- Longevity: Constant saturation can undermine decking, coping, and soils around your shell.
- Water quality: Runoff can wash mulch and soil into the pool, spiking phosphates and debris.
- Warranty & maintenance: Good drainage reduces callbacks and protects your investment.
The Three-Layer Approach to Pool Drainage
Think in layers: surface flow → subsurface capture → emergency relief.
- Surface Flow (Deck Pitch & Channels)
- Subsurface Capture (French drains, gravel trenches)
- Emergency/High-Water Relief (sump pit + pump, hydrostatic relief)
When these work together, water leaves fast—and stays gone.
1) Surface Flow: Deck Pitch Done Right
Recommended Pitch
- Target 1/8–1/4 inch per foot of slope away from the pool on hardscape (concrete, pavers, porcelain).
- Keep water moving toward deck drains, yard drains, or lawn areas—not back toward coping or the pool beam.
Deck Drain Options
- Linear/slot drains: Clean look along edges or transitions.
- Point drains: Round/rectangular in low spots; tie to solid pipe.
- Channel at thresholds: Where patio meets lawn or at doorway transitions.
Pro tip: On windy sites or tight yards, add a second collection line at the deck perimeter to intercept water before it reaches planting beds.
2) Subsurface Capture: French Drains & Gravel Trenches
Surface pitch handles visible water. French drains handle what you can’t see—water that migrates through soil or bedding layers.
What Is a French Drain?
A perforated pipe in a gravel trench wrapped with fabric. It intercepts groundwater and routes it to a safe outlet.
Basic build sequence:
- Excavate trench (commonly 6–12 in. wide, deeper than surrounding base).
- Line with non-woven geotextile fabric.
- Add several inches of washed angular gravel.
- Lay perforated SDR or corrugated pipe with holes down.
- Backfill with gravel to within a few inches of grade.
- Fold fabric over the top; finish with soil, mulch, or decorative stone.</span >
Where to Place French Drains
- Deck perimeter: Between hardscape and planting beds.
- Slope bottoms/retaining walls: To relieve lateral water pressure.
- Low corners of the yard: To collect and route water to a discharge point.
Do: Maintain continuous fall (1%–2%) in the pipe to discharge.
Don’t: Tie pool backwash directly into storm drains without local approval.
3) Emergency Relief: Sump Pit & Pump Systems
On high-water-table lots or heavy clay soils, a sump pit provides a fail-safe.
Sump System Basics
- Sump basin set near the low point of the yard or equipment pad.
- Inlets from French drains and yard drains.
- Submersible pump with check valve to prevent backflow.
- Discharge line to an approved outfall (daylight, storm system, or dry well per local code).
Why it matters: During long rains or spring thaws, a sump lowers local groundwater, protecting paver bases, concrete slabs, and the soil around the shell.
Downspouts, Gutters & Hardscape Interfaces
Keep Roof Water Out of the Pool Zone
- Extend downspouts underground via solid pipe past the pool deck’s influence zone.
- Add leaf filters/cleanouts to prevent clogging.
- At interfaces (house-to-patio), use a linear drain to capture roof splash and door-threshold water.
Hydrostatic Pressure & Relief
Pools displace soil. After heavy rain, groundwater can push up on the shell (hydrostatic pressure). To mitigate:
- Hydrostatic relief valve (in the main drain on many concrete pools) can allow groundwater into the pool to equalize pressure.
- Sump well adjacent to the deep end offers a place to monitor and pump groundwater before draining for service.
- Never fully drain a pool without professional guidance and groundwater checks.
Soil, Base & Backfill: The Hidden Heroes
- Compacted base layers under decks and pads reduce settlement and ponding.
- Angular, washed stone promotes drainage beneath pavers and porcelain systems.
- Geotextiles separate soil from base to prevent fines migration.
- Edge restraints (pavers) keep borders tight so water flows as designed.
Winter, Freeze–Thaw & All-Season Considerations
- Expansion joints where materials meet (pool coping to deck, deck to wall).
- Positive slope on all surfaces even after frost cycles—inspect and correct low spots.
- Snow management: Use plastic shovels and pool-safe de-icers; keep drains open.
- Covers: Automatic or safety covers reduce water and debris reaching deck drains.
Where Does the Water Go? (Discharge Options)
Always follow local codes before choosing an outlet:
- Daylight to a lower part of the property (with erosion control).
- Municipal storm connection (permit may be required).
- Dry wells/rain gardens (sized to soil percolation rates).
- No cross-connections to sanitary sewer unless explicitly permitted.
Troubleshooting: Common Drainage Symptoms & Fixes
|
Symptom |
Likely Causes |
Fixes |
|
Puddles on deck |
Insufficient slope, settled base, clogged drains |
Re-establish pitch, clean/upgrade drains, lift/reset pavers |
|
Mulch washing into pool |
Downspouts dumping near deck, no edge drains |
Extend downspouts, add linear/perimeter drains |
|
Wet planting beds year-round |
No subsurface capture; heavy clay |
Add French drain to daylight or sump |
|
Efflorescence on coping/pavers |
Trapped moisture migrating salts |
Improve subsurface drainage, breathable sealers |
|
Water in equipment pad |
Low pad elevation, no trench drain |
Raise pad, add trench drain tied to outfall |
Sample Drainage Specs We Love (Project-Dependent)
- Deck pitch: 1/8–1/4 in/ft away from pool toward drains.
- Perimeter French drain: 4″ perf pipe in 12″ gravel trench with non-woven fabric, 1% slope to outfall.
- Sump system: 18–24″ diameter basin with 1/3–1/2 HP pump, check valve, and dedicated discharge.
- Downspouts: 4″ solid pipe to daylight beyond pool zone, with cleanouts.
- Edge protection: Drip edges and gravel bands along planting beds to reduce splash-back.
(Your site’s soil, elevations, and code requirements will dictate final specs.)
Cost Snapshot (Planning Ranges)
- Linear/point deck drains: $35–$75/linear ft installed (system-dependent)
- French drain (4″ perf + gravel + fabric): $25–$50/linear ft (access/soil vary)
- Sump pit & pump (installed): $1,200–$3,000+ (distance to discharge matters)
- Downspout reroutes: $40–$75/linear ft (underground solid pipe, cleanouts)
Budget ranges vary by access, soils, distance to outfall, and hardscape type.
The Sunset Pools & Spas Drainage Blueprint
When we design your pool, we also engineer the watershed around it:
- Survey & elevations: Confirm high/low points and runoff paths.
- Hydrology plan: Deck pitch, drain locations, and French drain layouts.
- Downspout integration: Keep roof water out of the pool zone.
- Subsurface details: Base layers, geotextiles, and relief strategy.
- Commissioning: Test drains and pump operation before finish.
Result: a pool that looks great and stays dry underfoot—season after season.
Get a Drainage Plan Built for Your Yard
A great pool is only as good as the drainage around it. Sunset Pools & Spas designs and builds pools with deck pitch, French drains, and sump systems tailored to your soil and elevations—so your space stays safe, clean, and beautiful.
Contact Sunset Pools & Spas today for a free consultation or quote.
Inground Pool Drainage — FAQs (French Drains, Deck Pitch & Sump Systems)
Do I really need a French drain around my pool?
Not always, but it’s smart on clay soils, sloped yards, or anywhere water lingers. It protects bases, decks, and planting beds by moving water away from structures.
What deck slope should I use around a pool?
Plan 1/8–1/4 inch per foot of pitch away from the pool toward drains or lawn for consistent runoff and dry, safe walking surfaces.
Where should sump pumps discharge?
To an approved outfall—daylight, storm connection, or a properly sized dry well—per local code. Never into the sanitary line without explicit permission.
Can bad drainage void warranties?
Yes, it can. Improper pitch, clogged drains, or chronic saturation can cause issues outside normal wear. Good drainage protects both the finish and the structure.
Can you fix drainage on an existing pool?
Yes. We can add linear drains, French drains, downspout reroutes, and sump systems—even after a pool is built.