What is a drainage box?

What is a Drainage Box?

A drainage box is a type of catch basin used to collect rainwater runoff from your roof or other surface. A drainage box collects stormwater runoff and stores it until it can be released into the landscape when needed. A drainage box can also serve as a place for garden plants to grow during dry periods.

Drainage boxes are made up of two parts: a bottom and top. The bottom part contains gravel or sand to absorb the flow of water and prevent flooding. The top part may contain rocks, bricks, concrete blocks, wood slabs or even plastic sheeting to protect against floods.

They can also be made out of metal or even PVC pipe.

The main purpose of a drainage box is to capture excess rainfall that falls onto your property during storms. Rainwater runoff is normally not allowed to run off your roof because it can cause damage to your home. Instead, the excess water should be stored in a drainage box so that it does not harm your property.

How Do You Build a Drainage Box?

There are many different designs for building a drainage box depending upon its size and location. Some of these include:

Smaller than 1/2 acre (0. When the excess rainwater runs off into a drainage box, it helps keep your home dry during times of heavy rains.

Types of Drainage Boxes

There are many different types of drainage boxes available. Some are designed specifically for use with lawns while others are suitable for all kinds of landscapes. You will need to decide which type best suits your needs based upon where you live and what kind of landscaping you want to create on your property.2 hectares)

Add gravel or sand to the bottom of the box. Roughly 1/3 full is sufficient.

Medium sized boxes (1/2 acre – 2 1/2 acres)

Dig a hole that is wider and deeper than the box size. For instance, if building a box that is 8 feet long by 4 feet wide and 1 foot deep, dig a hole that is 12 feet long by 6 feet wide and 3 feet deep.

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Drainage boxes come in a variety of materials. They can be made out of steel, plastic, wood or even concrete. Each of these materials has its own advantages and disadvantages so you’ll want to weigh these carefully before making a final decision on which one to buy.

Concrete boxes may be the most expensive but they last the longest and are also the most durable. They are usually made from heavy duty reinforced concrete so they don’t break easily.

Once you have dug the hole, place your box in the bottom of it. If you are using wood planks instead of a manufactured box, place pieces of plywood or strong sheets of cardboard in the bottom of the hole to prevent the wood from rotting. Fill in the rest of the hole with soil and pack it down firmly.

Add more soil until the hole is full and level off the top. They may also be the most ecologically friendly because they do not have plastic or wood so they do not harm the environment. The only real disadvantage of this type is that it can be quite expensive.

Metal boxes are generally less expensive than concrete but they are often not as durable. They can rust over time which weakens their structure and they may become damaged more easily if they are placed in a location where there are a lot of kids or animals.

Plastic drainage boxes are the least expensive and are fairly easy to find at most big home improvement stores. They are not as durable as metal but they resist rust so their appearance doesn’t deteriorate as quickly. They may also come in a variety of colors which can blend in well with some types of landscaping.

Metal and concrete boxes are heavy so you will need a truck or a few strong people to carry them to where they need to go. Wood and plastic boxes are much lighter and can generally be carried by 1 or 2 people if necessary.

Most drainage boxes come with an inlet and outlet at the bottom so that excess water can flow into and out of the box. They also have small holes or slits on the sides for water to filter through. The bottom of the box may also slope slightly from front to back so that the water is directed to the outlet.

Instead of digging a hole, some people bury their boxes in the ground just enough that they are level or slightly below ground. If the box is buried a few inches below ground then the soil will help keep it from drying out too quickly.

For wood or plastic boxes, you may want to place a layer of gravel in the bottom to help with drainage. Measure the inside dimensions of the box to give you an idea of how much gravel you will need. A thin layer spread across the bottom should work.

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For metal or concrete boxes, the bottom does not need to be covered in anything because it is already designed to drain properly.

Add amendments to your existing soil to improve its structure and nutrient content. Begin by tilling the soil to a depth of 12″ and then mixing in manure or compost to improve its fertility. Then, till the soil to a depth of 8″ and mix in the remainder of your amendments to prepare it for planting.

With your new plants in their prepared bed, your job is far from over. Each plant will need regular water and nutrients until it is established, which can take several weeks or even months. It is critical that each plant receives the amount of water and nutrients it needs.

However, most plants need far less water in the winter months so don’t overdo it.

Also, in a few months when the weather begins to cool down, the leaves on your plants will begin to turn brown and fall. This is natural and called autumn. Once all the leaves have fallen off the plants, you can remove them from their containers and plant them directly into the soil where they will remain for many years to come.

As the years pass your garden may need extra care to replace what the plants have taken, but with a little effort your garden can continue to provide you with sustenance for as long as you choose to maintain it. Enjoy your garden!


This garden was grown entirely with a little help from Mother Earth, common sense, and the advice of a few good books. I want to thank all those who wrote the books which helped me learn how to grow my own food. Especially anyone I might have inadvertently forgotten.

Most importantly, I want to thank my wife for supporting my efforts and taste testing everything I’ve grown over the years. This garden wouldn’t be possible without you.

Thank you.


This garden was inspired by and modeled after other container gardens I’ve seen online. I wanted to make sure that everything in this garden was based on something which I could find information about and was able to be found either in nature or in someone’s garage.

I only added 2 items to the list of possible materials: sand and perlite (although I did add more than just a little). Even the soil was taken from my yard. Everything else can be found at home or online.

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(Always be safe when using outside sources and try to get material from reputable places.)

The first step in container gardening is to find a suitable container. I used a 10 gallon (38L) plastic nursery pot that I got at a local greenhouse for about $12. In addition to this pot, I also purchased a bag of perlite, vermiculite, manure and compost mix.

(And the seeds and plant food of course).

This pot had 3 “root” holes (where the plastic was pushed out of the way when the plant within grew too large). I cut 1 of these out so that I could add a layer of perlite to the bottom of the pot for extra drainage. (More on that in a bit)

The soil which I chose to fill 2/3 rds of the pot was actually Fillmore Mix from J.L.

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