How to Control Gutter Runoff

Gutters do a great job of shuttling water from the roof out to the yard. Even the roofs on smaller homes collect a lot of water in a rainstorm, so directing it all away from the foundation is no small feat. But not all systems are equally effective, as some might struggle to get the gutter runoff far enough away from the home to prevent it from impacting the foundation or creating hazards on nearby sidewalks or walkways. If these sound like problems you face, this guide on gutter runoff will help.

Why Gutter Runoff Is a Problem

Across a wide roof, rainwater and melted snow run down the shingles and collect in the gutter. From there, all the runoff heads to one side of the gutter and flows down a downspout, discharging into the yard. If the water isn’t discharged far enough away from the home, it can saturate the soil around the foundation and eventually lead to moisture issues in the basement or crawl space.

Other runoff issues include soil erosion, as water rushing along the yard can wear away the soil, and lead to ice hazards if the discharge collects on hard surfaces and freezes.

So, whether it’s for the sake of the home, the landscaping, or preventing slip hazards, gutter runoff needs to be handled appropriately. Longer downspout extensions can help, but there are less noticeable solutions that perform even better.

Before You Dig: Call 811

The most effective runoff solutions involve digging into the soil and running durable piping. But before you dig, you need to call 811 and have the utility company come out and mark your gas, electric, and cable lines to ensure you don’t accidentally hit them during the process.

This is the most important step of this entire process.

Assessing Your Yard and Downspouts

When deciding on the best solution for your home, take a look at some of its characteristics.

• Does the yard slope away or toward the house, or is it perfectly flat? If it slopes away, a pop-up emitter is a good solution. If it’s flat or slopes toward, a catch basin or dry well system would work better.
• Is the soil sandy or heavy and packed like clay? If it’s sandy, water from a pop-up emitter will drain easily and disperse through the soil. If the soil is slow-draining, a catch basin is a more appropriate option.
• Are there gardens, patios, or walkways that you don’t want to disturb while digging and routing the runoff away? If you have these limitations, a deeper catch basin might be a better solution than a pop-up emitter.

The situation may vary from one side of the home to the other. Take some time to come up with the solution that best fits your needs and yard.

Solution 1: Install a Dry Well (Catch Basin System)

A dry well is a catch basin system that collects water in an underground container or basin with perforations punched in the sides or bottom. The gutter system directs runoff into the basin where it slowly disperses into the surrounding soil. This is a good solution for packed soil, flat, or back-pitched yards, or areas with limited space.

Tools and Materials

• Catch basin (dry well)
• Schedule 40 PVC pipe
• Marking paint
• Shovel
• Hammer
• Crushed stone
• Gutter/downspout connector
• PVC elbow fitting
• Landscape fabric
• Yard drain
• Downspout adapter

Step-by-Step: Installing a Dry Well

1. Plan out the catch basin’s location and the path of the Schedule 40 PVC pipe that will connect it to the gutter system and direct runoff away from the home’s foundation. Use marking paint to make layout lines for digging.
2. Carefully start digging. Use a shovel to carefully remove the sod layer in rectangular chunks and place them to the side for reuse later. Dig the catch basin to depth first (according to the manufacturer’s recommendation). Then, dig a trench from the downspout to the catch basin, about 12 inches deep.
3. Knock out the perforations in the catch basin using a hammer and then place the catch basin in the soil. Fill the bottom of the basin with around 8 inches of crushed stone.
4. Install a gutter connector on the pipe along with a short length of Schedule 40 (about 2 feet long), and an elbow fitting. Cut another piece of Schedule 40 to length, measuring from inside the elbow to a few inches into the basin.
5. Adjust the height of the elbow by pouring crushed stone under it until the stone can hold the elbow at the correct height. The pipe should slope slightly away from the house, with the downspout connection higher than the basin inlet.
6. Install the lid on the catch basin before covering it with landscape fabric. Cut a hole in the middle of the fabric and install the yard drain. Add some crushed stone around the catch basin and then backfill it with dirt. Reinstall the sod and water it into place. 

Solution 2: Install a Pop-Up Emitter

If the yard is sloped away from the home, or you have the room to move the drain wherever you need to, a pop-up emitter is a great option. These systems feature a spring-loaded flap that opens when water pressure builds up. Water then spills out of the emitter and into the yard. Once the water discharges, the flapper closes again to help keep debris out.

Tools and Materials

• Pop-up emitter
• Gutter/downspout connector
• Downspout adapter
• PVC elbow fitting
• Schedule 40 PVC pipe
• Marking paint
• Shovel
• Crushed stone

Step-by-Step: Installing a Pop-Up Emitter

1. Dry-fit your emitter system, including the gutter connector, the downspout adapter, the elbow fitting, and the discharge tubing. Lay it out so it reaches the area in the yard where you’ll install the emitter.
2. Use the shovel to outline and dig the trench about 5 inches on either side of the discharge pipe.
3. Remove the pipe. Use a shovel to carefully remove the sod layer in rectangular chunks and place them to the side for reuse later. Then dig the trench to the proper depth and pitch. The trench should be about 12 inches deep to start and should run about ⅛-inch down per foot to ensure proper drainage.
4. Reinstall the downspout adapter, elbow fitting, Schedule 40 PVC pipe, and the pop-up emitter. Adjust the height of the elbow by piling crushed stone underneath it.
5. Repeat the process at the emitter, adding stone underneath to bring it up to the level of the soil around it.
6. Check the pitch to ensure it’s still ⅛-inch down over a foot and then add crushed stone underneath the pipe to ensure it’s stable and won’t bow under the weight of the water and soil over top. Check for slope once more.
7. Backfill the trench with soil and reinstall the sod, watering it after installation.

Maintenance Tips for Long-Term Drainage

While these systems are relatively low maintenance, you can’t ignore them. They can clog just like a gutter system can, so staying on top of their maintenance is key to ensuring they operate properly. Maintenance includes:

• Inspecting the system at least twice a year.
• Cleaning debris from the emitter or basin through the drain.
• Ensuring the emitter is free to move and seats completely when there’s no water.
• Ensuring the pipes haven’t settled and affected the slope.
• Flushing the pipes annually as needed.

Protecting Your Foundation Starts at the Roof

Believe it or not, water is your foundation’s biggest enemy. It can handle the load of the home above it, but enough moisture in the soil around it can cause cracks, shifts, and moisture problems inside. But with a proper runoff management system in place, you’ll be able to keep your foundation safe and dry, and even improve how your yard handles excess water. A catch basin or a pop-up emitter might be just the answer.