Grading a complete hillside site is always interesting. Not only is every site different, but hillside grading leaves the design up to the imagination.
This single family house located in Silver Lake is getting a revamp. The house stays but most of the site will change. In this example a garage will be demo'd to place a planted slope. The trick to this is that we will be proposing a new short wall in place of the garage and tied the proposed slope into the existing slope.
Maybe someone is curious to see what I am looking at as the basic design gets layed out. First I went through the property and drew some lines where drainage pipes make sense. From there I found where I want the outlets to go to the street. If I was working on paper I would quickly sketch these lines out. Then I work my way back from the street seeing how to get the water going into these pipes. From there I start drawing lines to connect the slope where it would make sense to keep the flow of the existing planted slope.
Through a few iterations I came up with the green lines giving a nice and even looking smooth looking slope. The green lines also show the drainage pattern going up to a swale along the walkway. This gives proper slope to bring the water down the swales. From that point is an area drain or catch basin that will collect the upper portion. The key to this is bringing the pipes coming from the upper rear yard area cleanly to this point and going out to the street.
If you can't read grading plans, the blue dashed line is the daylight line. This line shows where the join of the proposed and existing slope happens. In a perfect world the excavator or whatever they will use to fill the garage area in will be filled right to this blue dashed line, daylight, limit. I have matched the daylight into the existing toe of slope so there is an obvious place to start filling in.
The design takes longer than it looks because so many things are happening all at once. First you have to make sure that the drainage works. You don't want a bunch of low points on the swale. I only want one so we use as little drainage pipe as possible. Less drains to clog also means less maintenance. The slope must stay less than 2:1 as that's our limit. And if I can, which I did here, I want to make the slope as flat as possible evenly through the new fill area. We also want a good join point so the daylight line stays perpendicular down the slope. This allow for less chance of erosion as the new planting matures and holds the slope up.
At this point this portion of the design is done. The time consuming part is placing elevations in as many places to make building this as easy as possible. The finished product will be absolutely littered with text, creating what I like to call the text plan. The plan checkers like to see even more text than I normally show. And the guys going out to build, want to see a little less than I originally show.
This is a good example to show what hillside grading looks like on a grading plan, as the plan hasn't been destroyed by the elevations that will shortly be coming into plan view.
If you need a Landscape Architect, Terremoto is absolutely brilliant.