https://www.srevilak.net/wiki/index.php?title=ABC_Stormwater_Flooding_Group_-_May_14th,_2019&feed=atom&action=historyABC Stormwater Flooding Group - May 14th, 2019 - Revision history2024-03-29T12:26:29ZRevision history for this page on the wikiMediaWiki 1.41.0https://www.srevilak.net/wiki/index.php?title=ABC_Stormwater_Flooding_Group_-_May_14th,_2019&diff=739&oldid=prevSteveR: initial revision2019-05-18T00:41:06Z<p>initial revision</p>
<p><b>New page</b></p><div>Three people attended tonight's meeting: Wayne Chouinard, myself, and<br />
a fellow from East Arlington named Derek. We didn't have<br />
representatives from Cambridge or Belmont, meaning there wasn't a<br />
quorum.<br />
<br />
The three of us had a nice informal talk about the challenges of flash<br />
flooding -- think of a torrential downpour that drops a lot of water<br />
in a very short time. In a hilly area, these storms have the<br />
potential to turn roadways into rivers. Waterflow at the street edge<br />
can be wider than storm grates, and flows quickly enough that much of<br />
the water passes over the grates anyway. Water pressure inside the<br />
storm drain system can build up rapidly enough to dislodge manhole<br />
covers downhill. This has happened several times in the heights. Our<br />
roadway drainage systems were designed to handle 25-year storms, but<br />
the "traditional" 25-year storm happens more frequently.<br />
<br />
Wayne tells us that the town is planning to install a number of<br />
infiltration trenches. These would be connected to catch basin<br />
outflows. The outflow would run into a length of perforated pipe, and<br />
the pipe would be buried in gravel. The design sounds similar to a<br />
septic system drainfield, but with a single pipe rather than a<br />
lattice. The idea is to store the initial rush of rainwater, and let<br />
it gradually discharge into the ground. Derek likened this to<br />
''capacitance'' (i.e., the way a capacitor stores and releases<br />
electricity).<br />
<br />
Finally, we discussed rainbarrels as a stormwater mitigation method.<br />
One could store the rainwater and use it for gardening. A barrel with<br />
a 1/8" hole near the bottom would also be effective -- it collects the<br />
initial flow from a gutter system, and allows it to slowly drain out.<br />
The lower flow rate is more easily absorbed by the ground.<br />
<br />
[[Category:Public Meetings]]</div>SteveR