Integrating swales and rain gardens

[benhameen]

I am working on a permaculture design for some friends. Right now I have an open space on a steep slope (which I have not measured) below a garage.
The intended use of this space is to plant 5-6 fruit trees. I have already constructed the swales along the contours to assist with watering the trees and other vegetation, as well as preventing erosion. The garage has rain barrels on 1 of 2 downspouts because of location and slope issues. Below the downspout in question, I have constructed a rain garden minus the plants.
Here is the issue I have been tossing around in my head. What is the most effective way to integrate the rain garden and the swales? So far I have a diversion from the rain garden into the upper most swale. From there the rain garden continues directly into the next swale. I recently moved to Charlottesville, VA and know the average precipitation is around 40 inches, but that may include occasional hurricanes and tropical storms. Because of that, I spread gravel and rocks below that swale to act as a spillway in case the 6" deep swale is inundated with a deluge. There is a third swale below that but above where the slope levels out. Does that sound like a logical plan? Would a continuous water garden be more effective? I know that only paints part of the picture, but any thoughts would be appreciated.
Benjamin Thornes

[MindFreeza]

Pictures?

[benhameen]

So it has taken me a while, but here are some photos of the rain garden and swales in question.

[benhameen]

We have since experienced several rainfalls accumulating .5 inches or greater. The rain garden has handled the water exceptionally well. Unfortunately, the fill where the swales are constructed consist mostly of red clay, thus reducing the capabilities of the swales to allow water to percolate into the ground. At some locations where the berms were slightly lower, the water overflowed and caused erosion after all my efforts. Vegetation is becoming established now and I have incorporated rocks of various sizes into the hillside to hinder further erosion.

[benhameen]

I have been fed up with all the rain we have been dealt so far this year. I understand this part of the country has been more or less in a drought status for several years and need the rainfall to recharge the aquifer. This excess amount of h2o has lead me to modify my swales, though. Instead of tilling, I drove rebar into the ground approximately 1.5 feet, pulled it back out, then filled the holes with sand. Tedious, I know! Some of my plants below the swales were starting to fade because they were sitting in standing water for extended periods. I dug them out, added gypsum and sand along with more organic matter to combat the dreaded red clay. Since the swales were not draining properly, I treated them as rainwater retention areas and created rain gardens on either side to act as a controlled overflow in the same manner as a pond would with a spillway. I figured that I must plan for the extreme rain events accordingly. Since we received a couple inches of rain in the past few days, I have not been able to work but will post pictures next week.

[dlollard]

sounds good, thanks for keeping us up to date.

it's hard to adapt when there are so many extremes!

Don