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If you are a member of LinkedIn and you are interested in stream and river restoration, I recommend joining the ASCE River Restoration TC group.  Over the years, there have been some great discussions swirling around restoration. Doug Shields recently posted this question:

“How do you design a stream channel for a project that includes channel reconstruction/reconfiguration?” The responses so far have been quite good and I look forward to reading more. Jim MacBroom was my former boss and his opening sentence is perfect: “The most important step is to have a clear understanding of the channel’s physical processes and how they relate to the project’s goals and objectives.” Clear, articulate and difficult to argue otherwise.

 

I don’t use this blog too much for advocacy, but on March 1, 2016 the EPA and USGS released a draft report whereby public input is being solicited. Have a read and let your scientific expertise on ecology, hydrology and anthropomorphic alterations to flow be heard:

http://www.regulations.gov/#!docketDetail;D=EPA-HQ-OW-2015-0335

REFORM stands for REstoring river FOR effective catchment Management. It’s a pretty cool effort and I’d recommend spending some time noodling around the site. www.reformrivers.eu

The publication ‘Final report on methods, models, tools to assess the hydromorphology of rivers’ can be viewed as a pdf here. It’s a little over 100 pages, but it’s worth the read as it focuses on monitoring standards and assessment procedures to characterize the consequences of river degradation and restoration.  The report contains the following chapters:

  1. Introduction
  2. Overall Methodological Framework
  3. Stage I: Catchment-wide delineation and spatial characterization of the fluvial system
  4. Stage II: Assessment of temporal changes and current conditions
  5. Stage III: Assessment of scenario-based future trends
  6. Stage IV: River management

The report is chock full of good information, useful graphics, and literature. I particularly enjoyed this summary table in chapter 6.

hydromorphological_restoration

ESRI has created it’s own social network for user’s of its software called GeoNet. Back in March, ESRI created a webinar titled “Community Maps for Hydrology” and can be viewed here. The entire video is 53 minutes. Viewers might want to fast forward to about the 22 minute mark where the speaker starts to talk about and demonstrate the watershed delineation and downstream trace tools.  If you have points on a stream in a watershed, it is a fairly straightforward affair to delineate a watershed in either ArcMap or ArcGIS Online.  The appeal to doing this workflow in ArcMap is that if the delineated watershed is in a geodatabase, it is easy to get an area straight from the attribute table.   The video also discusses maps that provide real-time stream gage data and how it is possible to get a hydrograph plotted just below the map.

ESRI has also updated Maps for Office to version 3.  The interface is a bit more modern. As for new functionality, I think one of the biggest additions is that users can have more than one map displayed for a given tab.  ESRI’s blog post on the update is available here.

Simon Dixon writes an excellent piece (admittedly published January 2014) that summarizes some of his PhD efforts in England that looked at how adding woody debris to a river in smaller catchments might effect flood conditions downstream in a more urbanized setting.  The results seem to suggest that the answer is a classic ‘it depends’.  On the encouraging side, it appears as though allowing floodwaters to innundate floodplain forests can help.   To quote “the real take home message is the restoration of floodplain forests to entire “subcatchments” of the main catchment always decreases flood peak height after 25 years of growth, and can have dramatic effects.”  Three cheers for forested floodplain restoration and connectivity!

The piece is an excellent read as are the other posts in The River Management Blog.

USGS updates PeakFQ

Well, it’s September and it appears as though this update was released in back in March.  In any event, the latest version of PeakFQ is now 7.1 and it is available for download here:

http://water.usgs.gov/software/PeakFQ/

Be sure to read the version history which will discuss the new functionality in the program.

You might also want to read about what the Subcommittee on Hydrology, Hydrologic Frequency Analysis Work Group’s piece on Determining Flood Frequency using Expected Moments Algorithm here:

http://acwi.gov/hydrology/Frequency/b17_swfaq/EMAFAQ.html

I live in Massachusetts and really am not terribly knowledgeable about Florida surface water hydrology. I do know that it is a flat state, it has karst geology and that groundwater plays an important role.  I lived in Northern California for a number of years and spent a good bit of time reviewing USGS gage data. The coastal terrain tended to be steep and storms off the Pacific were capable of dropping significant amounts of rain.  The first time I saw a gage’s stage reading increase by over 15 feet in less than a day I was rather surprised, but over time I became more comfortable seeing such rapid stage increases.

Florida recently experienced some staggering amounts of rainfall. I heard reports indicating 22 to 26 inches of rain falling. As such, I had to go to the USGS NWIS Florida site to get a handle on how the rivers were responding.  As of this writing (May 1st, 2014) a number of gages are currently coded in black which the USGS labels as ‘High’). The Shoal River response caught my eye as it reminds me of responses that look like a Humboldt County California gage might look after a Pacific storm hits.

The Shoal River near Mossy Head (drainage area 123 mi2) was running at 348 cfs (2.8 csm) the morning of April 29 and peaked during the late afternoon on April 30 at 7580 cfs (61.6 csm) .  You can also see that the USGS sent hydrographers to the gage during just prior to the peak. Well done USGS and I hope that life and limb were not risked to obtain these data.

348 cfs to 7580 cfs in a little over a day and a half

348 cfs to 7580 cfs in a little over a day and a half

The stage change in 39 hours was just shy of 14 feet!

Nearly 14 feet of stage change in a day and  half

Average stage increase on the rising limb on April 30 was 8.4 in/hour

As impressive as this storm was, the historic data at this site indicate five events that were larger than 8,000 cfs. Even though roughly two feet of rain fell, other storms and antecedent conditions in past have led to even greater storm runoff.

April 30th flood will be the new flood of record

The data indicate five previous floods that were larger

As fascinating as I find these data, this is the classic case of what I refer to as the “hydrologist’s dilemma”.  We find these rare events exciting and interesting, yet at the same time, many people are suffering and are experiencing a life changing natural disaster.  It goes without saying that my thoughts and prayers are going out to the people in Florida who are now facing the challenge of a post flood situation.  May your fellow neighbors, place of worship, elected officials, local businesses and insurance companies all be a source of inspiration and may you be a more flood resilient community in the end.

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