If there is any particular part of landscaping that I can get a little OCD about, its irrigation. Coming from a maintenance background, too many times have I been trying to work on a valve or access a manifold to find it buried in dirt or otherwise inaccessible due to poor design and management. Then you start noticing unorganized irrigation layout, improper watering schedules, and wonky design from step one to finish. I've run into so many landscapes with poorly designed and managed watering systems that I'm starting to think we are suffering from Crappy Irrigation Syndrome, as a county if not as a state and nation.
So I'm on a mission. A mission to right the wrongs, talk shop, and get us thinking about our watering methods and how important they are to the success and failure of a landscape. For the sake of our plants, our aquifers, and our wallets. All key components to irrigation systems, and also all suffering at the hand of bad design and management.
One of the first things I notice when I check out an irrigation system are the manifolds, or irrigation boxes. These are the headquarters for your water operation. Its where the valves that turn your water on and off are located, and they are almost always, a disaster zone.
When we open an irrigation box, we're usually doing it to check a valve, manually turn on water, or diagnose a problem. We can't do any of that if the box if filled with dirt. Dirt manifold. "Oh good, looks like you got some nice dirt in that box there. Lets go get lunch."
This is what irrigation boxes often look like:
This is what I want them to look like:
These are the steps we take to install or update an in-ground irrigation box. Above ground manifolds have a different set of rules, and I almost always recommend in-ground systems unless it doesn't work for a particular site.
1. # of valves
Keep the number of valves to each box proportionate to the size of the box. Fitting 5 valves in a small rectangular box means the valves will be pushed up against the edges, and won't be accessible to do repairs unless you dig out the entire box. In small boxes as seen above, we don't do more than 3 valves, and keep them as centered as possible so we can work in the box without needing to spend extra time removing the entire thing.
2. Line the box
As I mentioned, most boxes are filled with dirt. This happens because gophers, winters, and nature in general push the soil up and around the manifold. Before placing the box around your valves, install gopher wire, landscape fabric and finally fill the the box with rock. Be sure not to add too much rock so you can work easily. Without these measures, a newly installed box could be filled with dirt within months (atleast here in northern California where gophers are rampant).
3. Mark your valves
A well designed box will have each valve numbered or somehow marked to correlate the valve to the station on the timer. I even like to add a description if possible to make it easy to locate the zone that is being irrigated.
4. Dry wires
If the box is lined properly the wires will most likely be just fine. Keeping them bundled, dry, and easy to sort will make maintenance much less of a hassle.
From a maintenance perspective, its common sense to have a clean irrigation box. Who has time to dig it out every time there is an issue, and how many issues arise because a valve is sitting in wet soil, clogged, or otherwise malfunctioning because of its environment?
I encourage all of you to go out and open up an irrigation box at your house to see what it looks like. Watch out for spiders. And monsters.