How to Stop My Backyard From Flooding When It Rains

Wet spots in your yard are a nuisance and an eyesore. Grass will die if it’s underwater for too long. 

You can’t mow over wet areas, and everyone tracks mud into the house. Furthermore, if the wet area is close to your home, it can cause your basement to leak, or worse.

So what’s the answer? In this article, we’ll review the available options.

Backyard flooding is a sure sign of improper drainage.  Areas that collect the most water from the rain tend to be low areas at the bottom of a slope. Therefore, you must take note of which sites of your backyard flood the most heavily to provide proper drainage.  

Before you can determine how to drain an area of your yard, you’ll need to make some basic observations first. Where is the water coming from? Meaning, is it runoff from a neighbor’s yard? Is it sheeting off of your shed’s roof? Do you have too many rain gutters emptying into the same spot? Identifying the causes of excess volumes of water goes a long way toward choosing the solutions that are right for you.

Next, you’ll really want to understand why a particular spot is holding water. Is it a low spot in the yard that can just get landscaped so that it drains? Or do you have garden beds holding water and not draining properly? Maybe the terrain around your house doesn’t adequately guide water away from the homesite. These issues may require heavy changes in the landscape to address drainage issues.

Finally, you’ll want to know which way you can divert water so that it’s safely away from your home and that of your neighbors. Ideally, you’ll take excess water out to the street or local stormwater system and away from your home and your neighbors’. Now that you’ve thought about the causes of your drainage issues, here are some solutions that can help you move water away from your yard properly.

Reasons for Flooding on Your Backyard

Soil Problems

How well water soaks into the ground depends on the type of soil you have on your property.

The problem could occur if you have soil largely comprised of heavy clay or a compact material. It will naturally be less absorbent, which can lead to drainage issues.

Improper Grading

The “grade” of your lawn refers to how it slopes. With proper grading, the land should be highest at the base of your house and slope downward as you get farther out, preferably leading to an alleyway, storm sewer, or street.

Unfortunately, not all lawns have this superior grade–especially backyards. This brings problems since perhaps you’re in a neighborhood where your backyard is separated from that of another homeowner only by a fence. If both lawns have been graded to slope away from your respective houses, water is more likely to pool at the fence line. Alternatively, many lawns simply contain (or develop) specific low spots that allow water to build up after it rains.

Thatch Issues

Thatch refers to the organic debris on your lawn that exists between the green vegetation at the top and the soil’s surface below. Thatch can include all kinds of matter, both living and dead: grass clippings, leaves, roots, shoots, stems, and so on.

The problem comes because for water to drain appropriately, moisture needs to soak into the ground. If there is a thick layer of thatch covering your lawn, this process can become much more complex, causing water to pool on top rather than seeping into the soil.

Hardpan

It’s not just the soil that you need to worry about, but also the subsoil–basically, the ground underneath the topsoil, which only goes down a few inches. Hardpan is a thick, dense subsoil that is practically impervious, and it can occur naturally or get accidentally created by construction vehicles.

The Problem: Water can’t soak into the hardpan, so it will drain down through the first few inches of topsoil, then basically just sit there and build until it comes back up through the topsoil and pools on your lawn.

Water Table Too High

You probably know that the earth is saturated with water deep under the ground. It’s why people create wells. Dig down deep enough in just about any area, and you’ll hit groundwater. The depth of this groundwater is called the water table–in other words, the water level under the ground.

The Problem: In short, the water table is a lot higher in some areas than in others. If you live in a place where the water table is close to the surface, drainage can be difficult because there’s just nowhere for the water to go when it rains.

The following are the most common yard drainage solutions:

Dry Wells

Dry wells are a yard drainage solution in which they are perforated tanks surrounded by aggregate that receive water piped from other areas. The underground plastic wells collect the water and slowly release it. This system can ingest a large volume of water and contain it so that the soil doesn’t become supersaturated. An effective dry well should be able to collect the first 20 minutes of your most extensive average rainstorm of the year. 

How to Build a Dry Well

Choose a Location.

The best place for a dry well depends on its size and purpose, but it should never be closer to the house than 10 to 12 feet. As a rule, you should choose a well-draining location that is low enough to allow water to flow into it by gravity.

Dig a Hole.

Size the hole to guarantee that it can handle the expected flow of water. For example, a 12-inch-diameter hole that is 3 to 4 feet deep would probably serve a single downspout, while a dry well catching water from a network of drainage pipes needs to be much more significant.

Dig the hole with a shovel, a post-hole digger, or an auger depending on the diameter and depth you need. 

French Drains

French drain systems solve drainage issues by collecting excess water in a perforated pipe and dispersing it evenly in the soil. 

To install a French drain,well-catching follow these steps:

  • First, identify where you have standing water in your yard.
  • Next, use a shovel to dig a trench in that area that leads to a place where the water can more easily drain.
  • Line the trench with pea gravel.
  • Purchase a French drainpipe or simply get a plastic, flexible landscape pipe. If you use a general landscape pipe, perforate it with holes and cover it with landscape fabric, leaving both ends of the pipe open to encourage drainage.
  • Place the pipe in the dug-out trench, making sure that the trench is deep enough that the top of the pipe does not reach ground level.
  • Cover the pipe with dirt and additional pea gravel, so it blends in with the rest of your lawn.

Gutter Downspouts

The gutters on your home could be contributing to the mass of water collecting in your yard. As your home’s gutters collect rain, they eject it through the nearest downspout. If your downspouts are emptying into an area that runs uphill or tends to collect water, it might be time to redirect your gutters.

You can attach a rigid drain pipe to the end of a gutter spout to carry water away from problem areas. Or, if it’s feasible, simply dig a dry creek bed for your gutter to empty into that will carry water away from problem areas.

Sump Pumps

Many homeowners install sump pumps to prevent flooding in their homes as well as their yards. Sump pumps are more effective for avoiding backyard flooding than French drains or dry wells but are also more expensive.  They work by removing the water from the soil and collecting it in their specially dug pits.  Once the hole is full, the water is pumped away through a drainage pipe that drains the water at a safe distance.

Foundation Drains

Foundation drains consist of drain pipes buried around the base of the house near the foundation; the pipes are perforated and laid in gravel bed. Foundation drains intercept groundwater and roof runoff as it infiltrates the soil toward the foundation and disperses the water over a wide area. In some cases, foundation drains are connected to the municipal storm sewer system to route runoff off the property and into storm drains.

Storm Drains

Storm drain pipes, drain grates, catch basins, and trench drains are components of a below-ground storm drain system that catches runoff water from your property and allows gravity to direct it toward your city’s storm sewer system rather than dispersing it on your property. Obviously, this type of system is only a possibility when your property has access to a municipal storm sewer.

Though front yard issues aren’t as prevalent, one problem specific to the front relates to having a sidewalk. If you’ve got one, it’s possible that it could be acting as a dam and preventing water from draining out of your yard. You can solve this issue by:

  • First, remove or cutting away part of the sidewalk to let water through.
  • Piping water underneath.
  • Routing water across the yard to an area with better drainage.

Other Drain Solutions for various places on your compound include:

Adding plants. 

Incorporate plantings, especially in areas where runoff collects. As water run off soaks into soil, plant roots help to absorb and filter out pollutants. When runoff soaks into and percolates through soil, the soil also acts as a filter, removing some pollutants.

Protect trees. 

Like other plant roots, tree roots help absorb and filter runoff. Tree canopies also slow rainfall and spread it over a larger area.

Break up slabs. 

Replace concrete patio slabs with pavers, flagstones, or bricks that allow water to soak in between items. For driveways, consider using a turf block or leaving a strip of grass up the center.

Go permeable. 

Choose an absorbent material for a path, patio, or driveway.

Less expensive options include aggregate base, gravel, mulch, or crushed shells. Pricier options include porous concrete or asphalt.

Catch runoff. 

Install a rain barrel or cistern to catch stormwater runoff from roofs. Use this water to irrigate garden plants.

Plant a rain garden.

 A rain garden gets designed to catch and slow runoff. It gets frequently planted in low areas, at the base of a slope, or near downspout outlets. The design includes soil layers, mulch, and plants, all of which filter rainwater as it seeps into the soil. Check with your local Cooperative Extension System office to learn rain garden basics.

Cover soil. 

Depending on the type, bare soil can be like concrete in terms of its ability to absorb water. Cover bare soil with mulch or a ground cover to slow stormwater runoff.

Swap lawn. 

Trade turf for native plants, which are adapted to local growing conditions and require fewer inputs (once established) than turf.

Drive on the grass. 

If your driveway isn’t permeable, wash your car on the lawn so water can soak into the soil instead of running into the street.