From @eworld.com Wed Mar 27 14:41:50 1996

The first thing you need to do is make some type of contour map of the area you want to retain and also the area around it. This is done for two reasons, first because you need to know how high each wall will be and also how long. These dimensions may change according to the design you want for the walls. Secondly it is so you can provide proper drainage around the walls. You will be altering the route of runoff water and you will want to divert it to desirable areas.

As far as materials go, there are basically three different types - natural stone, preformed concrete block (i.e. Keystone) and timbers. Of course stone and concrete block will last forever but timbers will hold up for 20 - 30 years and if you have a wooded site, maybee this is the look you want for your home. Sturcturally speaking, all of these, if built right, are strong, however, natural stone can only be used effectively if it is a short wall (under three feet) - unless you are using very large stone. The cost for purchasing these material range as well.

In my area of the country (near Chicago), these are the prices and so forth:

Keystone block costs about $5.00 a block for the full size block (a full size block is 1 Face Foot). The caps for the top of the wall are around $2.00 or $3.00. Then you need pins to hold them together (two per unit) which are about $.25. The gravel for the base is a CA-6 or crushed limestone with fines, and the backfill is 1" crushed stone. This type of wall is very labor intensive and if you were to contract the work out it would be $11.00 or more per Face Foot of wall.

Cut Limestone or Drywall Limestone measures 2" - 5" thick (you can get it in a 2"-3" or 4"-5" range), by 8" wide by 2' to 4' long. The cost per ton ranges greatly. If I were to by more than 20 ton I would order it from Wisconsin and pay about $185 a ton delivered. If I got a small er quantity I would get it from a local supplier but it would be almost double the cost per ton. The same CA-6 base applies here but you can backfill with topsoil as long as you have weed barrier behind it and drain tile.

Timbers are a nice choice and are a little cheaper. 6" x 8" x 8' Blue Tag Yellow Pine are the best to get but you can get Oak or other material. They cost around $19.00 in my area. Dead men should be at least four foot back with a four foot "tee" on it. The "tee" should be nailed to the top and not on the but end of the dead man. your dead men should start on the thrid row and be every other row. They should be placed between every timber on the row you place them. This seems like a lot but your wall will not fail. Topsoil can be used as backfill with fabric and drain tile and it is best to use a CA-6 base but the dirt will be good enough.

I hope this wasn't too much for you. If you have any questions e-mail me.

M. Erickson