Re: [ECOLOG-L] Flooding and stream geomorphology question from Vermont (response from Vermont resident)
Yes, in our area as well it had been quite wet before the storm came. Apparently when hurricane Bob (I think that was the one) passed through Vermont, it came into the state during a severe drought. I get the impression that late summer and early fall are usually quite dry, so again, we are looking at bad luck and/or climate changes. We were worried about the wind also. The wind almost completely failed to materialize in the Middlebury area, especially considering that last November we had a wind even with somewhere near 100 MPH wind gusts, and over the winter we had several nor'easters with much more wind than Irene. We also recently had a severe thunderstorm with much higher winds and tree damage than Irene (as well as 2 inches of rain, probably adding to Irene's flooding later). It's true that the soils were wet (not frozen) and the deciduous trees were fully leafed out, but still, we had virtually no tree damage here. On Tue, Sep 13, 2011 at 9:07 AM, Ann Poole wrote: > Hi, Charlie, > > Also contributing to the flooding during Irene (here, anyway) is the fact > that the ground was already saturated from several weeks of rain. We had 5+ > inches here and, with no storage available, it ran off in a flash. Brooks > rose feet in a matter of minutes taking out historic structures that had > stood for 100+ years or more. Thank goodness there was plenty of advance > warning though I think most people living on hillsides above the floodplains > battened down against wind, not really thinking about flooding. > > Ann > ~*~ ~*~ ~*~ ~*~ ~*~ ~*~ ~*~ ~*~ ~*~ > E. Ann Poole, MSc, CWS, Principal > Poole Ecological & Environmental Consultancy > PO Box 890, 741 Beard Rd > Hillsborough, NH 03244 > (603)478-1178 > e...@gsinet.net > www.eannpoole.com > ~*~ ~*~ ~*~ ~*~ ~*~ ~*~ ~*~ ~*~ ~*~ > > -- Charlie Hohn Recent Graduate Field Naturalist Program, Department of Plant Biology University of Vermont naturalist.char...@gmail.com slowwatermovement.blogspot.com
Re: [ECOLOG-L] Flooding and stream geomorphology question from Vermont (response from Vermont resident)
In the late 1800s Vermont was mostly covered in farms. Even mountainous ares with thin, erodible soils and pitifully short growing seasons were cleared for farms and pastures. The effect was dramatic - severe erosion, loss of soils, loss of arable land... People began realizing around the turn of the century that it was a bad idea to farm in Vermont uplands especially when the Midwest and later California became available for farming. The floods of the 20s hit recovering, but still heavily damaged watersheds. Runoff was more intense from the thin soils and less developed forests. The Winooski river hit ridiculous heights - I think it was near 30 feet at crest from Irene but the 1927 crest was over 50 feet at Winooski (near Burlington). Irene did not get nearly as bad on main stem rivers but in some cases in the upper watershed this flood was worse, just because the rain was so heavy (and the month had already been a wet one). Vermont does not have the immense system of levees that many other states have. In many cases Irene saw rivers abandoning their normal floodplain and cutting new courses. Buildings that survived the earlier floods (in upper watershed areas) were destroyed. This is not a case of people being unwilling or unable to avoid flooding, for the most part. This was a geologic/climactic event that is either a once in a lifetime thing or a result of climate change. Granted there is work to be done and in mill towns and rural areas we need to think long and hard about where we rebuild. In our community there has been a lot of dialog about what to do and today was an interesting day when I found an excavator in a place I did not want or expect to see one. But for the most part people here (like many places) care very deeply about their waterways and their communities. The key is finding the balance where structures and lives are protected but beyond that rivers are not over-engineered in a harmful way due to knee jerk behavior. Rebuilding will bring some interesting dialog to the table and hopefully among the destruction we DO change how we look at our rivers. Sent from my iPad On Sep 12, 2011, at 4:51 PM, "Wayne Tyson" wrote: > Charlie and All: > > From Charlie's blog: > > Re: Manage for Healthy Forests > > While dealing with the current flood, there has been reference to older > floods, like theNew England Flood of 1927 . That flood dropped similar > amounts of rain to > > Irene but in many cases had much higher water flow. Why? Part of the reason > may be that in 1927 the forests of Vermont were still recovering from clear > cutting and > > hillside farming in the 1800s, and there was much less mature forest at that > time than the current day. Our forests have recovered since then, which > helped keep > > Irene's floods from being even worse. [end excerpt] > > > Why? I have zero specific knowledge of Vermont, but know a little bit about > the Southern California watersheds and flood of which Hohn speaks. The > principles, however, are the same. > > I used to demonstrate with a bunch of kitchen sponges and a big cookie-sheet. > Watersheds absorb a fraction of the precipitation, and when one takes away > that absorptive capacity, the runoff (Q) increases, creating a "spikey" > hydrograph. > > The first kind of absorption is interception; an enormous amount of water can > be held under tension on the surfaces of terrestrial features, and trees and > other vegetation hold the most. Free water flow rates are reduced by > stemflow, and the infiltration rate of undisturbed soil is much greater than > disturbed soil; in disturbed soil, smaller particles clog soil pores much as > "Stop Leak" used to stop radiators from leaking (percolating). That fraction > runs off, causing erosion (more disturbance and creation of silt loads, which > compromise stream/drainage capacity. Logging reduces the amount of water that > can be held under tension and the metering effects of stemflow. Clearcutting > compounds this phenomenon, both by removing the surface area for a fraction > of the precipitation that can be held under tension, and by reducing the > infiltration and percolation capacity through equipment disturbance. (This is > not an argument for or against logging; it is only a statement of facts that > interpreted as such by special interests who fear the facts will gore their > particular ox.) > > Urbanization tends to seal the watershed even more, including highways, > roofs, irrigated agriculture and gardens, etc. > > I'll stop here and possibly comment further on Charlie's blog. > > WT > > PS: I do not blame Vermonters for their suffering; most no doubt were > completely unaware of the hazard
Re: [ECOLOG-L] a non Ivory Tower view of invasive species
grants, jobs, news > [mailto:ecolo...@listserv.umd.**EDU ] On Behalf > Of Manuel Spínola > Sent: Saturday, 10 September, 2011 12:22 > > To: ECOLOG-L@LISTSERV.UMD.EDU > Subject: Re: [ECOLOG-L] a non Ivory Tower view of invasive species > > > With all due respect, are not we all invaders at some point in time? > > Best, > > Manuel Spínola > > 2011/9/10 David L. McNeely > > Matt Chew wrote: >> >> > We can compose effectively endless lists of cases where human agency has >> > redistributed biota and thereby affected pre-existing populations, >> > ecological relationships and traditional or potential economic >> > opportunities. Those are indisputable facts. >> >> The House Sparrow is in North America by human hand. >> >> >> > But what those facts mean is disputable. >> >> House sparrows are in serious decline in Europe, probably as an unintended >> consequence due to human actions. >> > >> > I see effects; they see impacts. >> > I see change; they see damage. >> >> Many people see a need to eradicate non-natives. At the same time, many >> people see a need to preserve natives. >> >> With regard to the house sparrow -- hmmm. . >> >> Where does the "arms race" that Matt mentioned further along in his post >> lead? >> >> mcneely >> >> > >> >> > > > -- > *Manuel Spínola, Ph.D.* > Instituto Internacional en Conservación y Manejo de Vida Silvestre > Universidad Nacional > Apartado 1350-3000 > Heredia > COSTA RICA > mspin...@una.ac.cr > mspinol...@gmail.com > Teléfono: (506) 2277-3598 > Fax: (506) 2237-7036 > > Personal website: Lobito de río <https://sites.google.com/** > site/lobitoderio/ <https://sites.google.com/site/lobitoderio/>> > Institutional website: ICOMVIS <http://www.icomvis.una.ac.cr/**> > > > > > > > > -- > Manuel Spínola, Ph.D. > Instituto Internacional en Conservación y Manejo de Vida Silvestre > Universidad Nacional > Apartado 1350-3000 > Heredia > COSTA RICA > mspin...@una.ac.cr > mspinol...@gmail.com > Teléfono: (506) 2277-3598 > Fax: (506) 2237-7036 > Personal website: Lobito de río <https://sites.google.com/** > site/lobitoderio/ <https://sites.google.com/site/lobitoderio/>> > > Institutional website: ICOMVIS <http://www.icomvis.una.ac.cr/**> > > > > - > No virus found in this message. > Checked by AVG - www.avg.com > Version: 10.0.1392 / Virus Database: 1520/3890 - Release Date: 09/11/11 > -- -- Charlie Hohn Recent Graduate Field Naturalist Program, Department of Plant Biology University of Vermont naturalist.char...@gmail.com slowwatermovement.blogspot.com
Re: [ECOLOG-L] a non Ivory Tower view of invasive species
t; >> > decisions on if and when it would be appropriate to intervene. > >> > > >> > > >> > > >> > On 9/11/2011 10:42 AM, mcnee...@cox.net wrote: > >> >> Mitch Cruzan wrote: > >> >> > >> >> (stuff cut) > >> >> > >> >>What about the South Florida tropical flora/fauna? Many > >> >>> species in those systems only arrived on this continent only within > the > >> >>> last 5000 years - are they invasive? Are entire communities in the > >> >>> everglades invasive? > >> >> Hmmm. How long ago did Florida emerge? > >> >> > >> >> Are you suggesting we should not be concerned about pythons in > Florida, because though they are relative newcomers by Florida standards, > all of the Floridian biota constitututes newcomers by geological standards? > As another poster said, perhaps it is invasive behavior that matters. But > of course, these snakes are not invasive -- they are tightly tied to the > conditions where they evolved. They were brought by people, then released. > But they do wreak havoc on native fauna once present. Not a problem, since > Florida is recently emerged, so has only recently arrived biota? > >> >> David McNeely > >> >> > >> > > >> > > >> > - > >> > No virus found in this message. > >> > Checked by AVG - www.avg.com > >> > Version: 10.0.1392 / Virus Database: 1520/3890 - Release Date: > 09/11/11 > >> > > > > > > > -- > Malcolm L. McCallum > Oceania University of Medicine > Managing Editor, > Herpetological Conservation and Biology > > "Peer pressure is designed to contain anyone with a sense of drive" - > Allan Nation > > 1880's: "There's lots of good fish in the sea" W.S. Gilbert > 1990's: Many fish stocks depleted due to overfishing, habitat loss, > and pollution. > 2000: Marine reserves, ecosystem restoration, and pollution reduction > MAY help restore populations. > 2022: Soylent Green is People! > > The Seven Blunders of the World (Mohandas Gandhi) > Wealth w/o work > Pleasure w/o conscience > Knowledge w/o character > Commerce w/o morality > Science w/o humanity > Worship w/o sacrifice > Politics w/o principle > > Confidentiality Notice: This e-mail message, including any > attachments, is for the sole use of the intended recipient(s) and may > contain confidential and privileged information. Any unauthorized > review, use, disclosure or distribution is prohibited. If you are not > the intended recipient, please contact the sender by reply e-mail and > destroy all copies of the original message. > -- -- Charlie Hohn Recent Graduate Field Naturalist Program, Department of Plant Biology University of Vermont naturalist.char...@gmail.com slowwatermovement.blogspot.com
Re: [ECOLOG-L] Flooding and stream geomorphology question from Vermont (response from Vermont resident)
Hi, I study (among other things) watersheds and rivers and flood policy, and I live in Vermont (and in fact was an evacuee) so perhaps I can offer some other thoughts on this. I fully agree with the points people are making that people should not have built in the way they did in floodplains, that people should not try to control nature, and also feel that most floods are as much anthropomorphic (due to watershed degradation, etc) as natural disasters. That being said, the Vermont flood situation is VERY different. Our state is one of the most (re)- forested in the nation, and while we have our share of ecological problems like anyone else, our watersheds are in really good shape. In particular, most Irene flooding came from the Green Mountains, where orographic factors caused the rain to be the heaviest, and the Greens are almost entirely forest (preserved areas and timberland that is for the most part well managed.) Impervious substrates, type conversion, and so many of the other problems facing the United States are not major problems in most of these watersheds that had flooding. With the possible exception of climate change (though we can't say for sure with one specific storm), this is not a human-caused flood. I come from southern California, where the river systems are very flashy: most are dry for the entire summer, except for a few spring-fed creeks... but in winter, massive wet storms can dump 20+ inches of rain in the mountains, causing immense floods. (California is also dealing with lots of watershed degradation as mentioned above). When I moved to Vermont I was amazed at the old infrastructure - mill buildings, homes, etc, that were literally hanging into rivers. These aren't new buildings that keep getting rebuilt - these are buildings over 100 years old that did not wash away (except, in some cases, last month). Why? Vermont's winters have a well-deserved reputation for being cold, snowy, and harsh, but the summers are very gentle here. The 11+ inches of rain we had in Irene was a state record and a freak event... whereas in southern California our family cabin in the San Bernardino mountains got over 20 inches of rain in 24 hours, and the damage during that event was much less than the damage caused by Irene. We certainly need to change our relationship with rivers. If Irene is a climate change related even and we are going to get more storms like this, we absolutely need to rebuild wisely, and far from the rivers. But it's important to see this for what it is - a freak event (or sign of change) that had very little precedent - the massive Vermont floods of the 1920s and 1930s were as much a response to deforestation as to rainfall. Someone mentioned that 'all of Vermont is in a flood plain' but that is not actually true. Very little of Vermont is in a flood plain, but almost all of Vermont is prone to flash floods. The only places safe from flash floods are the immense old glacial lakebeds (and in part flood plains) of the Champlain and Connecticut valleys. Surprisingly, the swamps, lowlands, and flood plains that fill up with water every spring did not have record floods during Irene, and the water in some of the mainstem rivers wasn't much higher than during the spring snowmelt. This was an upper watershed event, and as such, a lot more complicated than people building in a flood plain. That being said, we absolutely need to take this crisis as also a teaching point, and make changes. I wrote a bit about that in my blog and will provide a link rather than posting it here since it is a bit long, but check it out if you're interested: http://slowwatermovement.blogspot.com/2011/08/preparing-for-or-preventing-next.html Thanks! -Charlie Hohn Slowwatermovement.blogspot.com
