We're at the tipping point for LID.
Efficacy is no longer an issue. After years of promoting low impact development practices because of their ability to mimic the natural processes of undisturbed landscapes, numerous projects, around the country, have shown the effectiveness of LID. Federal policy is shifting to incentivize LID/green infrastructure. And Portland's Mayor, Sam Adams, is using new funding strategies to achieve both stormwater and bicycle mobility objectives.
But still there is resistance to widespread adoption of low impact development facilities like bioswales and porous pavements.
One of the more intractable issues is maintenance and operations. Private developers are often concerned that LID presents a maintenance nightmare. And public utilities--which have been some of the pioneers in implementing LID--may not be confident in having the funding resources to maintain and/or establish the plants used in so many LID facilities.
Thanks to Seattle Public Utilities and Seattle Housing Authority, we've had the opportunity to update High Point's Right-of-Way and Open Space Landscape Maintenance Guidelines bi-annually, and have worked with the various maintenance companies to train them on the intent of LID. It is definitely different than most landscape maintenance regimes, but different does not mean more. Different means different.
Let's take one example, mulch. The first bioretention swales that were installed at High Point in 2003 started with compost then applied standard bark mulch to protect the plants, control weeds and retain moisture--that was until the heavier rains came and the bark mulch appeared to migrate or floating away. We moved to topping with compost yard mulch and now several years later they are topping with arborist wood chips from on site tree pruning. Lesson learned.
Widespread adoption of LID is going to absolutely critical to retrofitting our developed landscape and repairing the Sound, which is why we've been sharing our technical guidelines on the website. Please use them, we need to move quickly beyond the obstacles and make LID the new normal.