Day 14 3/23/2015
Today we began the implementation phase of the project. I decided to start with the back yard, leaving the front yard and driveway open for storing materials like gravel and concrete blocks. My biggest challenge at this time is trying to figure out how every step and element in the process fits into space and time. What needs to be done first? What materials do I need now and where will I out them? I want to make sure that I don’t miss any important steps and be forced to go back and re-do work we have already done. A project of this scale is a bit overwhelming to look at all at once, so I decided to break it down in a web chart similar to the one we created before the design process. I wrote down every major element of the project, and surrounded it with the tasks and materials that would be needed to complete it. I could then see what was required for every different piece at once, and make connections where similar materials were needed for different elements. Using this web chart as a reference, I was able to write out a rough flow chart of the steps involved in implementing the back yard design. I am sure that I will be making slight changes to the order of tasks, but at least now I can see what needs to be done right now, and have a rough idea of what is next, when I will need materials, and what needs to be done before we can move forward. I was feeling somewhat stuck and overwhelmed at the beginning of this day, but now I feel a lot more confident about completing the project. While I was working on the implementation plan, Carol-Anne got began the first task in the backyard, which is removing the decorative rock border around the pool.
Day 15 3/24/2015
Today we continued the work of removing the rock border from around the pool. We moved the rocks to the front yard where they will likely be used in the green strip succulent garden as a decorative mulch. We also began to excavate the existing irrigation pipes around the back yard, as most of them will be removed and the new irrigation lines will need to be installed at a lower level, beneath the future swales/infiltration basins. I carefully excavated around the irrigation control valves and hose bib, so I could see where each valve led to. There are some water and gas lines leading to the garage that I began to uncover as well, so I could ensure that we do not damage them accidentally while digging the swales. When this was done we began to scrape out a level path on the side yard for the hexagonal tiles to be laid into for a new path.
Day 16 3/25/2015
Today we began installing the hexagonal tile path along the side yard. This was a good project to get started on while we source materials and finalize our plan of action for the back yard. I purchased a 1/3 yard bag of sand from Home Depot the night before, which we used as a based for the tiles to sit on. The dirt path was leveled and then packed with a tamper, and then the sand was poured on, spread and leveled. The sand was packed with the tamper and then the tiles were placed on top. I found that it was very important that the tiles were settled evenly into the sand and well supported, as they are fragile and easily cracked if there are voids beneath them. Once all of the tiles were in place I used a push broom to spread sand into the cracks between the tiles. I then sprayed water over the path to help the sand settle into the cracks. These steps were repeated a few times until the cracks were well filled, leaving the path well settled and the tiles firmly supported. I am quite pleased with how the path turned out, the tiles make a beautiful pattern and the path makes the side yard much more inviting.
Day 18 3/27/2015
Today was a lot of heavy work. We started by digging out more of the existing irrigation lines, as well as digging a trench for the future grey water irrigation line beneath the fire pit area. The dirt we are removing is being wheelbarrowed to the south west corner of the yard to be stored for now. Later, much of this dirt will be screened and combined with compost to fill in the growing beds and in between the concrete pavers. In the afternoon, we took the truck to pick up a load of broken up concrete blocks that were posted in the free section of Craigslist. It was a lot of work loading and unloading the concrete from the truck, but these pavers are free and are being recycled instead of ending up in a land fill. Buying new pavers would be easier, but there is a huge amount of energy used in manufacturing and transporting those pavers to the store, not to mention the price. We are expending a little of our personal energy to prevent a lot of wasteful energy eslewhere.
Day 19 3/28/2015
Today we continued to dig out the existing sod and dirt in preparation for the concrete block pavers. We started next to the house on the east side of the pool, and will move around the pool from there. Again, this sod and dirt was moved to the south west corner of the yard. We constructed and used a “bunyip” water level to shape the dirt into the appropriate slope for drainage away from the house and towards the infiltration basin, using the level concrete slab around the pool as a reference point. We also dug a new trench for the irrigation line that will water the trees along the south fence. This was filled back in and the dirt packed down with a tamper. I called a local rock and gravel supplier and found out that the gravel we need to place below the concrete paving stones will be one of the biggest materials costs for this project, as we need quite a lot of it for the large area of pavers we are going to install. I again checked in the free section of the local Craigslist and found a few people giving away gravel from their yards. We drove out to one of these houses to get some free gravel, but unfortunately found that much of it had already been removed from the yard, and what was left required laborious scraping and shoveling. It was almost not worth the time and gas spent to get there, but thankfully there was a section of gravel in the back yard that had not been removed yet, and we quickly made up for the time spent scraping in the front yard. We got home and laid down a few concrete blocks as a test. It certainly looks like we have a lot of work ahead of us.
Day 20 3/29/2015
Today we had our first experience laying down the concrete pavers, which will eventually take up most of the space in the yard. We started at the top split of the “watersheds” in the design that will direct rain water into the different infiltration basins. This split is located at the south west corner of the house and will direct water either towards the south side of the pool, or along the back of the house and towards the north side of the pool. I found that laying out the concrete slabs is a time consuming process, especially in this area where the slope and elevation of each slab is critical to direct the water flow. This is also the widest area needing to be filled with pavers, so it takes a lot of them to fill the space. I am hoping this process will go faster in the skinnier sections around the pool. We also continued to dig and level out the dirt moving away from the house and towards the north side of the pool. We used the water level quite a bit as i wanted to make sure the water from the outdoor shower I plan to install will flow towards the vines that will grow over the pergola. This shower, if used frequently, should provide al the water these vines need. An outdoor shower was a much simpler method of delivering household grey water to the back yard than re-piping the house showers.
Day 21 3/30/2015
Today we continued to level out the dirt in front of the patio and north side of the pool, moving the dirt to the southwest corner of the yard. In front of the patio the slope of this watershed reaches the final level of the infiltration basin, which is 8.5 inches below the pool coping. About 4 inches of this will be taken up by the concrete slabs, plus another half-inch or so of gravel beneath them, leaving the walking surface of the basin 3.5 inches below the pool coping surface. One challenge with this infiltration basin is that, at its lowest point, the existing concrete slab on the patio sits 2.5 inches below the pool coping. If the basin were to fill up during a heavy rain event, the water could overflow onto the patio. To prevent this from happening, and to leave a little room to spare, I will have to make the over flow drain for this basin a half inch below the level of the patio. This puts the drain only 1/2 inch above the bottom of the infiltration basin, meaning only 1/2 inch of water can collect on the surface of this basin for storage after a rain event. I would like to be able to collect more, but this will have to do. I could make the basin deeper, but the walking surface would be too far below the pool coping, causing a trip hazard. As it is, the storage capacity of this basin 24.3 gallons, reached by the following calculation:
78 (aprx. sq. ft.) X 0.5(depth in inches) X 0.623 (conversion factor) = 24.297 Gallons
The total catchment area draining to this basin is approximately 970 square feet, meaning that for every inch of rain about 600 gallons of water is collected by this basin:
970 ft.sq. X 1 in. X 0.623 = 604.31 gal.
These calculations make it seem like an awful lot of water is being lost and not much is being stored. However, these calculations assume an impermeable surface such as a roof. Much of the catchment for this basin is made of the concrete slabs set on gravel, with soil in between. This surface will absorb a large amount of rainfall before it becomes saturated and water starts to flow over its surface towards the basin. The actual impermeable surface catchment leading to this basin is 648 square feet, meaning about 400 gallons will be directed to the basin per inch of rain. Also to consider is the fact that the average rain event in San Diego drops about 1/2 an inch of rain over a 24 hour period. So that leaves about 200 gallons being collected each storm, still farm more than the 24 gallons the basin can hold. However, 24 gallons is the amount of water the basin can collect on its surface. The 5 inches of soil and gravel between the concrete slabs will have to become completely saturated before any water will collect on the surface, and this is the real purpose of the basins, to store water in the soil between and beneath the concrete slabs. With the slow gentle rains that normally happen in southern California, I predict that the infiltration basins will rarely fill up. Of course, for those times when the rain does fall quick and heavy, the record being 3.24 inches in 24 hours, there will be the overflow drain leading to the last infiltration basin in the south west corner of the yard. This basin will be much deeper and have a much larger capacity.
Day 22 3/31/2015
Today I poured a new concrete step in front of the back door. As it was, you had to exit the house and turn right to step down onto the patio. Most of the time people would just continue forward out of the door and step down the large drop from the landing instead of using the step to the right. This is of course a bit dangerous, and Melissa said she has twisted her ankle before stepping down from the landing this way. I built a form out of some old fence boards and continued the step on the right around the front of the landing. This should make exiting the house much easier. While the concrete was setting, I prepared set in place the pier blocks that the pergola posts will rest on. These needed to go in before the concrete pavers, as they needed to sit on the compacted sub-soil and will be surrounded by the concrete. I will be leaving soil filled spaces near the pier blocks so that vines can be planted to grow up the posts. We also ran into a small problem while digging out the infiltration basin next to the pool. There was a large chunk of concrete underground that had spilled out from the pool coping form when the pool concrete was poured. I had to break this up with a sledge hammer to make room for the concrete pavers.
Day 23 4/01/2015
Today I decided to pour another concrete slab extending the patio out to the edge of the new stair. I felt like this would be much safer than having to step down onto an irregular concrete paver, and all the edges around it. I built another simple form and poured in the concrete. After I had smoothed out the concrete, of course, Max the dog walked right through it, so i had to do it over again and make a barrier around the slab with chairs and other objects. While I was making the new slab, Carol-Anne built a low retaining wall out of purchased concrete blocks, that forms the growing bed along the south wall of the garage. I decided to use purchased blocks instead of urbanite for this wall because the space between the pool and garage is already quite limited, and the blocks would allow for a thinner wall.
Day 24 4/02/2015
A few days ago I responded to an add in the free section of Craigslist for concrete chunks that would be delivered. Today the contractor showed up with a 2.5 yard dump trailer filled with concrete and dumped it in the front yard. He offered to bring another load, and considering the amount of space we need to fill with urbanite pavers, I accepted and he came back a second time. There is now a huge pile of concrete chunks in the front yard, most of which I estimate we will be using in the back yard. We may have to load whatever is left over in to the truck and bring it to a recycling center when we are done, but having this concrete delivered saved us from having to load the truck with concrete 6 or 7 times, and all the time that would require. Thank God for Craigslist! We also took a drive up to Mountain Meadow Mushrooms in Escondido this afternoon and picked up a truck full of spent mushroom compost. This mushroom growing operation has a huge pile of spent growing medium in their yard that is free for the taking, you just have to shovel it yourself. I plan to mix this compost with the existing soil to fill in between the pavers and inside the growing beds. I will be using whatever is left after completing the back yard to sheet mulch the front yard. This compost is full of mycelium, so I am hoping that it will help shift the soil biology towards more balance between bacteria and fungi, which will support bushes, shrubs, and trees instead of just weeds.
Day 25 4/03/2015
Today we filled in the first of the concrete pavers with soil. I built a compost and soil screen out of wood and 1/2 inch hardware mesh, and built a stand to suspend it from by utilizing some metal fence posts that were in the back of the yard. I connected the poles with 6 inch eyelet bolts and suspended the screen from chains so that it would hang just above the level of the wheelbarrow. This allowed us to screen the grass and rocks out of the existing soil, while mixing in some of the mushroom compost to add fertility and soil biology. Since we have such a large amount of native soil beginning to pile up in the back of the yard, I decided to mix 3 parts soil to 1 part compost in order to use more of the native soil in between the pavers. We sifted a few wheelbarrow loads of this soil/compost mix and raked it into the cracks between the concrete pavers. I soaked this thoroughly with the hose to help the soil settle into place. I want to make sure that the soil level between the pavers doesn’t fall over time, leaving trip hazards all over the yard. We will see how this mix works.
Day 28 4/06/2015
After a couple days off we are back at the back yard project. We laid in some more concrete pavers along the north side of the pool and in front of the patio. The first yard of gravel I purchased to spread beneath the pavers was 3/4 inch crushed rock. For this next section I purchased 3/8 inch crushed rock and found that it makes setting and leveling the pavers much easier. However, placing the concrete slabs is still quite a laborious task, and it seems that I will be doing this for longer than I expected. While I was doing this, Carol-Anne continued to dig up the sod and soil from the south side of the pool. We also prepared a few more loads of soil/compost mix to fill in the cracks between the pavers that have been laid. I found that the mix we used for the first section was very soft and took a few repetitions of soaking and drying out to settle into the cracks between the pavers. I decided for this next section to add in some of the 3/8 inch gravel to make a more solid mix. We used 2 parts soil to 1 part gravel and 1 part compost in this mix. We will see how it does.
Day 29 4/07/2015
Today we finished digging and leveling the infiltration basin on the south side of the pool. We again moved the dirt to the southwest corner of the yard, which is now gather quite a large pile of soil. I am hoping we will be able to put a lot of this soil back into the cracks between the pavers, and move the rest to the front yard to create topographic texture. After the leveling was finished I dug a new trench for the irrigation system and laid in the PVC pipes, as well as setting in a couple valve boxes at the level of the finished infiltration basin pavers. Although PVC is not the most environmentally friendly product, HDPE is a much “cleaner” plastic for irrigation lines, I am electing to use PVC for this project because I already have so much of it on hand from pulling out the old irrigation system. Nearly all of it is still in good shape and will be able to be recycled back into the project. We also began building the planter on the south side of the pool, laying the foundation with large slabs of concrete. Heavy work!
Day 30 4/08/2015
We spent the whole day today finishing construction on the urbanite planter. It is basically made up of a wall, 3 slabs high that encloses an area to hold soil. Even though we only did a wall three slabs high, it took all day to finish the planter. It was like a big, very heavy, jigsaw puzzle. Each piece has to fit neatly with the blocks around it, so a lot of time was spent moving slabs around, trying to find the right piece for a particular spot. Then, rocks and gravel were used to fill gaps beneath the slabs to ensure that they lay flat and don’t rock back and forth. Needless to say, we are very, very tired after this day of work, but the planter is finished.
Day 31 4/09/2015
More pavers! The pile of concrete in the front yard is getting smaller and smaller, especially after all the slabs we used in the planter. It looks like we may actually run out of pieces that are big enough, a big surprise after seeing the size of the pile when it was dropped off. I am starting to get pretty tired of working with urbanite, physically and mentally, but the job has to be finished. I keep trying to think of a different option for a long term, low maintenance surface for around the pool, but the urbanite pavers still seem like the best option, even though they are a lot of work to install. For some easy work at the end of the day, we began filling in the planter with soil from the pile in the back corner of the yard. We filled the bottom half with the native soil, and we will fill the top half with a 1 to 1 mix of compost and soil.