Thursday, August 27, 2015

A Seemingly Endless Supply of Broken Glass

Meadow trail with rising gibbous moon
I haven't posted in a while, so I just thought I'd let my followers know that I'm still around.

I really don't enjoy going outside when it's hot and humid, and it's been that way here for the last few weeks.  So, after working in my air conditioned office, I go home after work to my house (where I generally don't have to use the air conditioner because the thick stone walls keep the house tolerable), cook, eat and clean up after dinner, and then watch some television before Kali and I head to bed.  Pretty boring, huh?

However, last Sunday afternoon, Kali and I tackled a job she loves to do: pick up broken glass on a trail in my preserve.  This glass is not from malicious youths who bust beer bottles.  This glass is from the 1920s or earlier.  At that time, my preserve was farmed, and one of the farmers used a ravine as a garbage dump.  Now, the ravine is eroding deeper and deeper, and the broken glass is washing out of the soil onto one of our trails.  The glass drives Kali mad when she sees it.  So, we've been making periodic forays to the ravine and trail to collect the shards.  There are some really big pieces of glass, and most seem to have been parts of milk bottles.  Occasionally, we find pieces of what I describe as blue Delft-ware, but the fragments are always small.  Kali likes to go into the ravine and onto the trail after a rain because the water exposes debris after each storm.

On the way back home after our glass collecting expedition, we were crossing one of the large open meadows on my preserve and the sky was bristling with Common Nighthawks catching insects on the wing.  I love nighthawks, but only get to see them a few days a year during their fall migration.  So, last night after dinner I cajoled Kali to take a walk to see if the nighthawks were there.  They weren't, but the evening was really pleasant with relatively cool temperatures, low humidity, and clear blue skies, so we had a nice long walk. 

Monday, August 10, 2015

Suburban Stormwater Tour: The Good, the Bad and the Ugly

Los Angeles River East
My organization is partnered with four other watershed organizations in the Philadelphia suburbs in a consortium that is working to improve water quality and reduce stormwater quantity in the Delaware River.  Our consortium works in the Philadelphia suburbs, but the philanthropic foundation that spearheaded this work is funding seven similar consortia throughout the huge watershed.  Our consortium is tasked specifically with reducing stormwater, while the consortia working in less-developed parts of the basin are working to reduce agricultural impacts and to preserve open space. 

Our work has been going on for 1-1/2 years now, and the staff of the foundation requested a tour of sites where the foundation's support has been used to implement stormwater management projects in the field.  On Thursday, August 6, the watershed organizations' and foundation's staff members gathered for a day-long bus tour of four sites scattered throughout the Philadelphia suburbs.    

First stop was at a private residence where a rain garden had been installed.  This rain garden was one of about 20 rain gardens that are being installed in prominent locations where neighbors and passers-by can become familiar with using a rain gardens to capture and infiltrate stormwater running off impervious surfaces instead of allowing it to pour directly into storm drains.
Publicity in the front yard
The rain garden, planted in May
Homeowner (blue shorts) and project consultants (right)
Second stop was a detention basin created to manage the stormwater for a 40-unit McMansion subdivision in a wealthy neighborhood.  While the basin was larger than needed to manage the stormwater generated by the subdivision, the basin was poorly designed and actually did almost nothing to detain stormwater.  The municipality has committed to modifying the basin by reducing the diameter of the discharge pipe (thus trapping and holding the stormwater for longer periods of time), creating islands, peninsulas, and pools within the basin to create habitat, and planting native vegetation throughout.
On the berm above the basin (about 10 feet deep)
Temple University hydrologist explaining testing equipment to monitor project effectiveness
After lunch, we toured a municipal sports complex where stormwater sheets off playing fields and discharges directly to a small stream.  (Turf sheds water almost as effectively as asphalt.)  At this location, the municipality intends to create deep, rock-filled swales that will allow rainwater running off the fields an opportunity to soak into the ground rather than run off directly to the adjacent creek.
Water from the playing fields (right) and parking lot pours into this swale, then directly into a creek
Grass swale will be replaced with a rock-filled infiltration trench
Later in the afternoon, we stopped at one of the most challenging and intractable sites imaginable; we wanted to show the foundation staff members just what our organizations have to deal with in the developed suburbs.  Here, a small headwaters stream drains a fully-developed residential and retail neighborhood.  Because the watershed has so much impervious surface (e.g., driveways, rooftops, lawns, and roads), very little rain water soaks into the ground, so the stream has almost no baseflow during dry periods.  However, when it rains, the stream turns into a raging torrent because all of the imperious surfaces shed water directly to the creek.  Unfortunately, this neighborhood is densely developed, so the stream channel is located in residents' backyards and there's nothing that can be done to widen the channel or create stormwater detention.  Instead, the municipality confined the creek to a concrete channel reminiscent of the infamous Los Angeles River to sluice the water downstream as quickly and "safely" as possible. 
Concrete confines
During our last hurricane, two people living downstream of this channel drowned in their basement when the water rose up in a flash and flooded the house.  So much for safety.