Tuesday, May 15, 2012

Getting the Job Done

"Those irises are so pretty!" we hear frequently this time of year. 

Yes, they're very pretty.  Also very Ravens purple, making an attractive entrance on the south side of the complex.  But that's only part of the reason why they're there.

These hard-working irises, and their less flashy neighbors, the tough ornamental grasses, have an important job to do.  One they are very good at, as I saw this morning.

We had heavy thunderstorms last night and this morning.  Real gullywashers, as the farmers used to say.  When those torrents hit the acres of asphalt around us, the runoff drains into perimeter areas with tremendous velocity. 

This particular outfall, below Lot D, was a real problem.  It eroded after every downpour, leaving trash and parking lot detritus in the crevices.  In addition to being an unsightly mess where nothing could grow, it was also the landfill for beverage bottles discarded by the locals.

A few years ago, MSA applied some environmental engineering to the problem.  The soil was regraded, heavy rocks were placed below the drain, and the entire area replanted as a rain garden.  Those beautiful irises are the second line of defense against runoff, after the rock breakwater.  Their thatched tubors are firmly anchored so they won't wash away.  And unlike many species, they can handle damp as well as dry beds.  They flourish in watershed areas.

What you can't see in this picture is the three inches of water they are sitting in.  In another hour so, most of that will be absorbed instead of polluting the Middle Branch just below our complex.  The soil on the banks won't become silt in the river, because it is held in place by those grasses and their extensive root system.

At the same time this problem was addressed, another unattractive environmental challenge was met.  The steep slope between the stadium and train tracks, home to a colony of groundhogs who kept the surface unstable, was cleared of scrub invasives and rodents.  It was replanted with low maintenance, drought tolerant shrubs and grasses.  Within a year, purple butterfly bushes covered the area below the pedestrian bridge and the grasses anchored the problem area below the retaining wall.

(Yes, they're pretty, too.  And they smell wonderful in the late summer, when they're covered with migrating monarch butterflies.  But that isn't as important as their full time job, which is holding the bank in place.)

We haven't been able to do as much of this environmental planting as we'd like, because of the budget challenges.  But thanks to the Ravens and their home playoff appearance this year, we're able to do a little bit more this spring.  In a few weeks, there will be more perennials (purple, of course) on the hill, and new ornamental grasses to correct the failing swale along Ostend Street.  The irises, which have multiplied over the past three years, will be divided and replanted  into a larger spread.

So admire the beautiful flowers.  We all do.  But also appreciate them for the job they do so well.

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