Not much with the pond hole happened on Friday. Around 9 a.m. the electricians arrived and began working on the wiring. They added a new breaker and cleaned up some bad wiring, installed by the previous homeowner for the pump on the original pond. As you can see in the pictures, the vault wiring is almost finished. They will be returning tomorrow (Monday) to complete the job.

Saturday was beautiful and I spent the day finalizing the installation of the walls for the vault housing. I drilled 1/2″ holes in the top of the vault walls and installed anchors. This allowed me to bolt the housing to the top of the vault.  The vault housing is now attached permanently. I built the housing ahead of time so I would be ready. I choose redwood and normal CDX plywood for the walls. As most of you probably know, redwood is moisture resistant and makes a good building material for this type of project. Pressure-treated lumber should never be used near ponds because it contains chemicals that are harmful to fish. CDX plywood is rated for some moisture exposure, so it is also a good choice where moisture may be present occasionally. To make the housing more water resistant,  I coated external side of the walls with FlexSeal. When FlexSeal cures it is safe for fish and it comes in black, which will look good for how I will finish the exterior.

I built the pressurized air manifold a few months ago while we were still waiting for the project to begin. While designing this air system, I did a fair amount of research about the appropriate valve types to control air flow. The two most common valves you find in plumbing supply or big box stores are gate and ball valves. While these valves are great for on/off they’re not really meant for flow control. Most sources recommend needle valves or globe valves for controlling the flow of a gas or fluid. Large needle valves are hard to come by, and very expensive, so I chose globe valves to fine tune the air running to the bottom drain diffusers. As you can see in the photos above, there are unions after the valves. This type of union would not work for high pressure systems, but the Matala Hakko 120L air pump only runs at about 2.84 PSI so these will be just fine.

I’m looking forward to getting the wiring finished and hope the weather improves so the the Urban Escapes crew can work tomorrow.