Background and Structure

-A one rock dam is named so because it is one rock tall
-The dam should be several rows long, but only about 1/3 the height of the bank because it is meant to slow the water, not stop it
-Although most of these runoffs are found on hills, you should find a relatively flat spot to build your dam
-If you do find your self at a spot that is uneven, use the larger rocks to place to in larger swells
-Along with flood control in little creeks, it is also a good erosion control in runoffs
-Ceasing this erosion allows you to cause sediment deposition, water harvesting, nutrient retention, revegetation, and bank stabilization
-These also allow you to use the rain water for giving your plants water
-These one rock dams also cause good growth in the stream bed
-These rocks to construct the dam are place closely together, in parallel lines
-Although these dams are effective at slowing water, their purpose is not to cease the water completey
-They slow the water instead of stopping it completely because there is not a ton of exposed surface area of the rocks, so most of the water just runs over the top of the structure
-The excess water is left in the dam (or nearby) giving water to the roots of the different plants
-This is why the dams are able to have so much vegetation in between the rocks
-This extra vegetation also helps to slow down the movement of water because the roots hold the water more in place
-This extra vegetation also helps to bind the rocks to make the dam more resistant
-Since all of this slows the water down, there is less power in the flooding and the erosion is decreased substantially

-One rock dams are best suited for rocky drainages

-The maintenance for one rock dams is quite simple: replace the stones in the dam that have washed away in larger floods

-Also to make these dams as successful as they can be, you should plant different types of grasses in between the rocks because the widespread root system of grass is great at holding the rocks in place in case of a big flood

Check Dams

-Check dams are the type of dams that one rock dams fall in the category of

-Check dams and gabions are wire-wrapped dams that slow water which leads into a natural reservoir

-They slow the water, but do not cease it because the water is able to pass through it quite easily, just at a slower rate

-This allows the the water to seep into the soil much more easily

-So, the main purpose of check dams is to slow the water, so vegetation will grow and create a more scenic route in place of the natural drains caused by erosion

-One rock dams are the most easily check dams to build

-Even a large bed rock can create a scenic ephemeral spring, so imagine what a whole check dam could do

-And even though these dams help to slow water, they help dry creek beds be full once again

-Along with the more drainage into the soil, the slowly moving water leaves behind different nutrients that are key to the success of different plants

-The best place to put a check dam is in a dry creek bed or an arroyo so when the rain and floods come, the water is put to good use

Before and After Pictures of a One Rock Dam

(Click picture to view entire photo)

This shows the before and after pictures. As it is easily seen, the after pictures have extra vegetation to help slow the water down and also it looks much better.

A cross hatch of a one rock dam

6 Steps to Make a Check Dam or a One Rock Dam

1) To find a place to start, look for the highest point in the arroyo or the place of erosion, depending on how you plan on using the dam. Next, you need to find a runoff place, or a spill way where the small amount of excess water will go. If there is not an extreme excess of water, though, the spill way is not necessary, only a planned place of where the water would flow to.

2) Next, you must find the stones needed for you dam. The most effective way to format your dam is the following:

-A foundation of medium and small sized stones and rocks is needed as a base

-Then, you must place the largest rocks along the outside edges of the base in order to take the heavy damage from the fast flowing water

- Lastly, the outside of the erosive area or creek bed must be filled with stones in order to keep the erosion from increasing even more

3) The dam should be set at a slight arc. The stone walls closest to parallel to the flowing water, or the arms should be close to parallel to the running water. These arms are unnecessary in smaller projects, preventing erosion

4) These "arms" of the dam should be lower than the rest of the dam, so you should dig a small trench in the creek bed and fill these indentions with smaller pebbles and gravel until they are as high as the rest of dam. Like I said before, though, these arms are unnecessary to smaller erosion projects

5) Even outside of the arms, though, larger stones should put a "liner" on the creek bed's walls. Below these, though, it is necessary to place smaller stones in order to increase the siltation of the area

6) Repeat the process every several feet (depending on the creek bed) in order to slow the erosion and water down even more

Although this process is very exact, it is less so when building small one rock dam, where water does not flow as rapidly or as frequently. In these situations, it is just necessary to make sure that you make a dam one rock tall, but many long. This process is solely used for larger creek beds

Larger One Rock Dams

(Click on picture to see photo)

This is an example of a larger one rock dam, where more than one rock is used to create the height. You can make these using the instructions given above

Usage in Other Countries

-These techniques that I discussed earlier are used all over the world, but there are also other reasons for these one rock dams

-In Africa, there is a very little amount of water, so they need to use all of the rain fall that they receive

-So they are forced to used the little water that they receive

-To do this, they use the naturally formed valleys and arroyos and build one rock dams to save the little rain fall that they receive

-This helps to irrigate their fields and crops, as well as giving life to wild vegetation intertwined in the rocks