Water that pools next to foundations or discharges too close to a house is a common cause of basement leaks, damp basements, and foundation problems. The International Residential Code requires that finish grade fall a minimum of 6 inches within the first 10 feet away from the foundation unless an approved alternate (like a drain or swale) is provided[1]. In addition to code, federal and local guidance encourages redirecting roof runoff so it soaks into lawns, feeds rain gardens, is collected, or is routed to approved storm inlets rather than the sanitary sewer[2].
First checks and low-cost fixes to try first
1. Clean and inspect gutters
Start by removing debris and checking for leaks or disconnected sections. Clogged gutters overflow and concentrate water at the same spot every storm, defeating other drainage measures[2].
2. Ensure downspouts discharge away from the foundation
Make sure downspout outlets do not point at the foundation. Practical, low-cost options include splash blocks, corrugated flexible extensions, pop-up emitters, or burying corrugated pipe to daylight or a storm inlet. These measures keep concentrated discharge off the foundation and move water farther downslope[2][9][4].
3. Maintain positive grade where possible
Where site conditions permit, regrade the soil so it drops about 6 inches over the first 10 feet away from the foundation to meet the IRC requirement; if that slope can't be achieved, provide an approved alternate such as a swale or drain[1][9].
4. Follow local rules and avoid prohibited discharges
Do not route concentrated roof runoff onto a neighbor's property or into the sanitary sewer. Many municipalities prohibit connection of roof leaders to the sanitary sewer and some have mandatory downspout-disconnection programs with local guidance on acceptable alternatives[2][3][9].
When simple fixes aren’t enough: trench drains, French drains, and sump systems
If surface fixes (gutter cleaning, extensions, regrading, splash blocks) do not stop water from reaching the foundation, consider subsurface options:
French drain / curtain drain: a sloped trench with perforated pipe surrounded by gravel that intercepts and diverts shallow groundwater or surface runoff away from the problem area[5][6].
Interior perimeter drain: installed under the slab or against the footing to collect water that has already breached the wall or slab and route it to a sump basin[7].
Pros and cons
Properly installed French or curtain drains are effective at intercepting and moving water and at reducing hydrostatic pressure on foundations, but they can be disruptive and costly, may require a sump pump if gravity drainage is not available, and can clog over time without proper filter fabric and installation details[6][7][5].
Costs to expect
Consumer guides show wide cost ranges: shallow exterior French drains are commonly quoted around $10–$35 per linear foot, while deep exterior or interior perimeter systems can run much higher per linear foot and whole-house interior systems often total thousands to tens of thousands of dollars depending on depth, access, and finishes. Interior systems that need a sump and pump generally add additional costs[6][7][8].
Key components and manufacturer guidance
Choose pipe and fittings to match the application: solid pipe for surface conveyance, perforated pipe for infiltration/French drains, and follow manufacturer details for bedding, filter fabric, and jointing. Corrugated/perforated HDPE pipe (for example, ADS N-12) is a commonly specified product for buried conveyance and French drains; manufacturers publish installation and sizing guidance. Downspout adapters, catch basins, and product lines are sized to fit common downspouts and reduce debris entry where appropriate[5][4].
Sump pumps, electrical and code considerations
Interior perimeter drains typically terminate at a sump basin with a sump pump to discharge water where gravity outlet is not possible[7]. Installed sump pump jobs vary widely in cost depending on complexity and backup options[8]. Electrical and code requirements for basement receptacles and sump pump circuits are evolving and vary by jurisdiction; GFCI protection improves electrical safety but a tripped GFCI can leave a pump offline during a storm. Consult local code and a licensed electrician, and consider backup power or a backup pump where failure carries high risk[10][11][8].
Step-by-step homeowner action sequence
Clean gutters and inspect for damage or leaks[2].
Ensure downspouts discharge away from the foundation using splash blocks, extensions, pop-up emitters, or buried corrugated pipe to daylight or a storm inlet[2][4][9].
Regrade soil where possible to achieve ~6 inches of drop in the first 10 feet per the IRC; if that slope cannot be achieved, provide an approved alternate such as a swale or a drain[1][9].
If surface fixes are insufficient, evaluate exterior French/curtain drains or an interior perimeter drain that terminates at a sump basin and pump[6][7].
If using a sump pump, ensure the discharge complies with local rules, arrange appropriate electrical protection and consider backup systems[7][10][8].
Practical distances and local requirements
There is no single universal numeric distance in the IRC for how far downspouts must discharge. Common guidance recommends a minimum of 4–6 feet and some engineers or homeowner guides recommend 8–10 feet where practical. The controlling requirement is positive drainage away from the foundation and compliance with local municipal rules, which may have specific mandates (including mandatory downspout disconnection programs in some cities)[1][2][3][9].
When to call a pro
Hire a qualified contractor or licensed plumber/electrician for complex excavation, interior perimeter/sump installations, electrical work for sump circuits, or when local permitting is required. Complex interior drainage systems and sump installations often require coordinated trade work and can be costly and disruptive, so get multiple estimates and written scopes of work[6][7][8].
Bottom line
Start with the least invasive measures: clean gutters, keep downspouts discharging well away from the foundation, and regrade for positive drainage where feasible. If these actions fail to stop water problems, evaluate French/curtain drains or interior perimeter systems with sump pumps, following manufacturer installation guidance and local code/permit requirements. Always check municipal stormwater rules — many places require disconnection from the sanitary sewer and offer local guidance or programs[2][3][1].