I had an interesting sequence of thoughts after watching my 12-year old daughter chat with a friend on her cell phone about a music video they were simultaneously streaming on their laptops.  It’s easy to marvel at a kid’s fluidity with technology that didn’t exist when they were born, but I realized that I, too, experienced this rapid adoption of innovation.  I had my earliest music collection on LP, shifted to cassette tape and my beloved Walkman in middle school, moved to college with crates of CDs, and now carry the whole lot in my pocket on the same device that I use to take pictures, pay bills, and call the local Thai takeout place.  It got me wondering, as a stormwater engineer, what similarities my industry shares with others when it comes to the spread of new ideas.  When we generate new ideas, how well do we transition from initial innovation to general acceptance and widespread implementation?  One of the critical factors in this process seems to be the availability of support and maintenance services within an industry.  These innovations need to function reliably over time, and as many are too complicated for us to maintain ourselves, we depend on various support mechanisms such as auto mechanics and the helpful geek at the Apple Store to ensure this longevity.

Several weeks later, I was disappointed to see an example of how the stormwater industry suffers from a gap between the initiation and the support.  I pulled into my community gym to see that the pervious concrete drive aisles were being demolished and replaced with interlocking pervious paver blocks after only 10 years of operation.  This is a city-owned facility, and I’ve watched over the seasons as silt, moss, and tree litter have slowly but steadily filled in the surface pores.  I’ve noted which parking spots to avoid as the action of automobile tires has caused raveling and rutting over much of the lot.  The operation was proceeding efficiently, and the new pavement looks fantastic (see below for a before and after comparison), but it is unclear if the same level of porosity and infiltration capacity can be achieved.  It’s also unclear if the admission fees for the swimming pool will remain the same.  Standard estimates place the cost of paver blocks at around twice that of pervious concrete per square foot, and a brief call to my city’s capital projects manager indicated that this replacement falls at the high end of the estimate scale. 

Now clearly, stormwater infrastructure development is not directly equivalent to the telecommunications industry, but it seems that the trend of technical support following the spread of innovation should still be applicable.  This is not the only example of failed pervious pavement in my community, prompting me to wonder why the operation and maintenance hasn’t followed the material’s initial adoption.  A couple answers spring to mind:

First of all, the implementation of stormwater BMPs is not solely beholden to the consumer market.  Regulatory drivers encourage the use of certain techniques over others in pursuit of public water quality goals, and local stormwater agencies direct developers in their implementation.  This is rightly so, but while my gym utilized pervious concrete to help satisfy their permitting requirements, they were not compelled or sufficiently incentivized to purchase the $150k regenerative air sweeper truck recommended for routine maintenance.  This seems a clear disconnect (and an opportunity for someone with a CDL and a very large garage).

Secondly, these BMPs are owned by a relatively small group and go largely unnoticed by the general public.  Even though pervious concrete has been in use within the US since the 1970s, and despite the spread of LID techniques generally, the public at large has not contributed to the customer feedback loop that demands improvements to more common innovations.  And while very good research has been done on the effectiveness of pervious pavement, this has largely focused on the installation techniques and the water quality benefits of the material.  Recent studies by Washington State University have reported on system maintenance, and the Oregon Department of Transportation’s Stormwater Technology Testing Center will be determining BMP lifecycle costs, so perhaps the focus is starting to shift.  Despite public outreach campaigns (and my own staunch opinion), stormwater BMPs simply aren’t perceived to be as sexy as a Bluetooth speaker that checks your email and makes coffee.

While my comparison has its limitations, one thing is clear:  we would not expect a cell phone to last in society if its maintenance plan consisted of replacing it at twice the initial cost.