When It Rains It Pours - Follow our stormwater sleuthing team for another successful performance of pervious concrete.Read More
stormwater management system
The last time that the category of El Niño was considered Very Stong was the winter of 1997-1998, where many California communities suffered from mudslides and flooding. This year's El Niño is showing signs that it could be even stronger. There is a strong chance that the Bay Area could see as much as twice the annual precipitation, maybe above 40 inches of rain. This could greatly impact the state by damaging homes, disrupting transportation systems, schools, and businesses - potentially costing state residents billions of dollars. Many cities are preparing for the additional rainfall by cleaning out their waterways and storm systems. California officials are warning people to prepare for potential flooding conditions. You may be asking, "What can I do to reduce the risk of flooding for my home or business?"
One thing you can do is by replacing sidewalks, driveways, parking lots, patios, and roads with pervious concrete. Luckily, installing pervious concrete is one type of El Niño preparation you may be able to receive a rebate for. Saving you money upfront and in the long run!
The internet has been calling this pervious concrete "Super permeable" and Magical." If you agree, you don't have to travel to the UK to see it or have it! Bay Area Pervious Concrete has been installing super pervious concrete management systems for nearly a decade. This viral video, from the UK firm Lafarge Tarmac, is a great representative of how fast pervious concrete can infiltrate water, but how does pervious concrete handle longer water events - like heavy rain storms? A real life test of pervious concrete. In our Stormwater Sleuthing video David compares two driveways after at least 12 hours of steady rainfall.Read More
We have been working with architects, engineers, homeowners and municipalities to really explain how pervious concrete is a comprehensive storm water mitigation device. It has proven difficult to help people to wrap their heads around how allowing water to soak in to where it falls, using pervious concrete, is a viable storm water management strategy - so we have started to use Dynamic System Modeling as a tool to help explain what is happening in a pervious concrete slab, and how much water it can infiltrate over time.
When we use the concept of infiltration over time, pervious concrete systems provide huge capacity, far exceeding most climate’s most intense storm events. That is most easily demonstrated using a software modeling system. This allows insight as to a system’s capacity, and informs design, to ensure that the pavement and drain rock base will meet or exceed the required storm water infiltration amounts.
Contact us for a consultation on your project or to schedule an office presentation to learn more!
David Liguori is back in the field, this time comparing a long sloped asphalt driveway with a neighboring long and sloped pervious concrete driveway during a rainstorm last year.
What did you think? Do you have a Stormwater Sleuthing location (in the Bay Area) that you would like David to investigate the next time it rains? Let us know in the comments below or contact us here. Thanks!
This was originally posted June 19, 2013.
Lauren Wray, our Director of Marketing, attended the USGBC’s Greener Builder Conference last week. Apparently the Greener Builder Conference is even GREENER then the Green Builder Conference that occurred in November! This conference did not disappoint. From the opening panel, pictured below, featuring Jeffrey A. Birdwell, Michael Deane, Kevin Hydes, Kirsten Ritchie and moderated by Cliff Brewis, the focus was on leading edge sustainability, and strategies to get regenerative planning and innovation into the building industry.
There were good options for every panel, but as pervious concrete sub-contractors, we went to the subcontractor panel, hosted by John Home and Jeff Swinyer of Rudolph and Sletten, pictured below.
Lauren, pictured below, was interested in the drive toward clear performance specs to allow for differentiation at the sub-contractor level. As a pervious concrete subcontractor, we differentiate ourselves with our embrace of leading edge technologies for mix design and installation. Unfortunately, many current specs don’t reflect the progress in the installation, mix designs, equipment and curing materials that has developed in the last few years.
The next panel we attended discussed Environmental Product Disclosures (EPDs), a labeling system that discloses the resource footprint of the many materials that go into the built environment. The panel also included the next iteration, the Health Product Disclosures, which discloses the materials and chemicals that have been proven or correlated in causing health problems for humans.
Central Concrete, a sponsor of the event, has been heavily involved in the EPD project for disclosing the materials for the concrete industry. Below is a photo of the panelists from this panel.
The last panel of the day went over Net Zero Energy buildings with John Andary and Scott Shell, pictured below. It was a fascinating look at what is currently possible with technologies now: buildings that use as much energy as they make. The building case studies discussed also illustrated how livable and workable these spaces were, with thought for passive heating and cooling. Many of the designs features windows that bounced daylight far into the building envelope, as well as fresh air ventilation. It was a wonderful talk, even though their topics stayed primarily inside the building envelope.
The final speaker, Jason McLennan, pictured below, gave a wonderful talk on self limits. His talk really stood out for his candor and optimism. For a young guy, has accomplished quite a bit in the green building spaces. Currently he is pioneering the Living Building movement.
After his talk, Jason McLennan was joined by George Salah, of Google, and David Gottfried of the USGBC. They discussed everything from George’s living-building home construction project to Jason’s motivation to do the work that he does: “I give a shit.” That was wonderful.
FInally, after it was all over, we found that there was a fantastic array of beers, wine and snacks to round out the day’s networking. It was a great event, and one we will look forward to attending next year!
A BIG thank you to Charlie Nucci, who took these photos at the event. You can find more about Charlie and his work at his website here.
Check out the most recent thinking about pervious concrete across the United States with great photos, articles and advertisements from local pervious experts in your area. PerviousPro is the brainchild of Dale Fisher and the people over at the NPCPA - the National Pervious Concrete Pavement Association. We even have an article written by Bay Area Pervious Concrete.
Check out this issue here:
Let us know what you think!
We at Bay Area Pervious Concrete have come a long way towards developing the Pervious Concrete as a viable Stormwater Management System. Going through this diagram, you can see where the water goes -- one of our most frequently asked questions.
Starting at the bottom-SOIL
We do soil infiltration tests before our jobs so we can understand how fast the water will soak in, underneath the pervious concrete. Once we understand the infiltration rates and soil composition, we can engineer the appropriate depths to excavate for the next layer, the drain rock.
Before we lay the drain rock we sometimes will lay a layer of GEOTECH Fabric, which adds a helpful barrier against some less porous soil types. We determine the need for this during the soil composition and infiltration tests.
Now for the DRAIN ROCK!
Drain rock is laid several to many inches thick, depending on the rain event to be captured, the soil type below, and how much impervious surface is draining into this slab. It is a very specific type of drain rock, not the typical base used under concrete which is impervious - we want to maintain about 40% air space to both allow water to pass through and give it place to "hang out" if the soil has a slow infiltration rate.
Finally the PERVIOUS CONCRETE
The pervious concrete is then laid on top of the drain rock, screeded and rolled into place and covered in plastic, where it will cure for at least a week.
The client had flooding in the back and front of the house due to an uneven grade of the lot and excessive roof runoff.
Why Pervious Concrete?
He initially wanted a pervious concrete driveway because of impervious ground cover limitations in his city.
We designed a pervious concrete driveway and side yard that is also the retention pond for all of the roof and yard runoff.The pervious concrete water retention system captures 100% of their runoff from the roof AND the lot. They now have a dry front yard, back yard and they can grill just off the kitchen without puddles!