We have been using pervious concrete paving for about 10 years now. In case you are not familiar with the product, I came across this clip that sums it up pretty well.
Our success rate is pretty good, as long as we have had a decent drainage system underneath the concrete to allow the water to percolate back into the aquifer. It’s also important to keep sedimentation buildup off the surface of the concrete, as it blocks the voids and essentially cancels out any benefits.
As far as the sedimentation buildup, here are a few things we’ve learned along the way:
- Isolate the pervious concrete from the different sediment sources surrounding the paving. In other words, slope these surrounds away from the concrete.
- Maintenance of the pervious concrete is substantially reduced if you use 1/4″ or smaller clean stone in the mix. This will increase concrete strength while still providing sufficient void space. Ensure the batch plant washes any sand or fines in the drums of the trucks before batching the pervious concrete.
- If you can, conduct a test pour for each load of concrete delivered to ensure the finished mix meets the project specifications. A quick unit weight test prior to concrete placement will verify the mix is consistent and within the specs.
One other item–and we’ve not tried this yet –but we have heard that color can be added using either a liquid or a powder integral color. The pictures look very nice, and it’s on our “to try” list.
