(from Joel)

When we first moved into the house, I immediately began thinking about building a retaining wall along 20th and Kearny Street to add up to 15' of yard on both sides. After mowing the grass on the sidehill a few times, I was completely convinced. The wall was really a low priority, but the huge amount of dirt generated by the basement project made the wall a logical next project.

Almost three years later, the retaining wall has arrived, and it looks like it will be the first major project to be completed.

The Labor Day weekend looked to be the right time to take on the project. The weather in September starts to cool a bit, and the humidity is less oppressive. I started out by renting a mini-excavator, which made short work of the footing trench.

Friday was also a day to get everything delivered and staged. I needed about 40 tons of gravel for this project and a couple other drainage issues. The last time I had gravel for the basement delivered by dump truck, it made a hell of a mess of the sidewalk, yard and street. It also really limited where I could put the gravel.

This time I paid a little extra and hired a company called Stone Shooters to deliver the gravel for me. They use trucks commonly called "stone slingers" which can put the stone anywhere it needs to go.

The stone slingers have a hopper on the back, connected to a remote controlled conveyor belt. They can shoot the stone up to 100'. I pointed to two flat spots in the yard where I wanted stone. In 10 minutes or so, I had two 15 ton piles of crushed blue stone. Easy and fun to watch. All in all, I probably paid a $200 premium to get these two loads delivered, but the convenience of not needing a permit to dump it in the street and being able to distribute the gravel where I needed it was worth the money.
After traveling the week before, then following me around all day Friday, and having piles of stone and pallets of concrete block delivered, Baker was pretty beat. He decided to take up station on a pile of dirt while I dug the footings with the excavator.

The system of blocks we used is called a Segmental Retaining Wall (SRW). SRWs are a great alternative to a concrete or mortared block wall because they are dry stacked. That means you don't have to put a footing below the frost line. Around here, that saves you 2-3 feet of digging. If the ground below the wall freezes and heaves a bit, the wall moves with it. When the ground thaws, the wall just settles back into place. A concrete wall built above the frost line would crack and fall apart.

The first step is to set the first row of blocks below the ground on a 6" bed of compacted stone. In this picture you can see the raised bumps on the top of each block that properly position each course of blocks back 1/2" from the course below.

At this point, I should mention that each of these blocks weighs 94 pounds. Lifting the blocks isn't too bad, but positioning them down in the trench is really hard. You don't just drop the blocks into place either. The first course must be absolutely perfect. Any imperfections in the first course will be visible all the way up the wall. This means positioning a block 5 or 6 times to get it just right.

Here you can see the second course of blocks, which in this case is the first course above ground. The corner blocks have two finished sides.
You can also see how the gravel compacts into the voids in the SRW blocks. This locks them tight together.

On Saturday we did a short length of wall in the most inconspicuous portion of the wall. We got a good feel for how to set the blocks, and progress sped up from here.
We had two very nice guys from Guatemala helping on Saturday, and by the end of the day, they were totally trained in setting the blocks.

On Sunday our Guatemalan friends brought two more guys to move the project along. This is them setting the Kearny street base course. This probably took 5-6 hours to set 60 feet of base.

You can also see the materials set in the tree strip by the street. This is just the material for the Kearny Street side. The 20th street side had it's own stockpile.

Thankfully the Guatemalans were great guys, and really understood that perfection in the first course would pay off in the later courses. This let me get to work on the drainage system and backfill behind the wall.

This little toy is commonly called a Dingo (this one is actually made by Ditch Witch, but Dingo is the original version of a mini-skid steer made by Toro). It's like a Bobcat that you can walk behind or stand on a platform on the back.


The Dingo is really compact and powerful, and although the bucket is pretty small, it can lift 500lbs of dirt or gravel at a time. It took me about 60-90 seconds to load, transport and dump the equivalent of 2 full wheelbarrows.

The tracks mean the Dingo has great traction and can climb hills really well, but it is still a bit tippy. I had to bail off the back once when I took it a bit too far on a sidehill. It didn't go over, but it took me a few minutes to figure out how to get it back out without killing myself or the $15,000 machine.

This is where we ended the day on Sunday. After setting the base blocks for 6 hours, the rest of these were set in about 3.

On Monday, we added another course of blocks to bring the wall to 4'. My permit says I can go to 3.5', so I'll go into the permit office and beg (and write a check I'm sure) for them to let me go one course higher. The difference is pretty big in terms of the slope of the yard. You wouldn't think 8" of height would make such a difference...

If they say no, that's fine, we'll just pull the top course off.


Here is where we ended on Monday night. The bulk of the wall is in. I have some detail work to do on the corners, and the new staircase on Kearny street will be it's own project. I'll probably wait until my Dad is here in October to tackle that. It'll just be a long Saturday project. We also have a low fence to put on top of the wall.

I'm planning to do some more grading and backfilling this weekend, then it's back to the basement. I'm hoping to have at least one bedroom finished by the time Jenn & Tristan visit us on the 20th.

Hun and I couldn't be happier with how the wall turned out. The difference in usable yard is huge. There's still lots of work to do, but the vision is there - we have a much better idea of where things will go, and though the yard is very public, it also has great discrete spaces for different purposes, whether that's a dog area, front yard, garden or patio.