Watershed Hydrology

<body background="art/frosty.gif" bgproperties="fixed" link="#FF8000" vlink="#006666" alink="#00FF00" text="#000080"> <div align="center"> <center> <table BORDER="0" width="640" CELLPADDING="5" CELLSPACING="0"> <tr> <td ALIGN="CENTER" colspan="2"> <h2 ALIGN="CENTER"><b><font face="Courier New" color="#FF8000">STORMWATER EVENTS</font></b></h2> </td> </tr> <tr> <td ALIGN="justify" colspan="2"><font SIZE="-1" FACE="arial, helvetica, sans serif"> <p ALIGN="JUSTIFY"><span style="font-size:10.0pt;font-family:Arial">On September 17, 2004, Hurricane Ivan deposited an average of 6.25 inches of rain in a 24 hour period over the already saturated clay soils of the 277 square mile Chartiers Watershed. On that date, Chartiers Creek crested around 11:00 pm at 23.98 feet, topping the banks in many low-lying communities.  Peak flow was 23,.500 cubic feet per second, or 175,000 gallons per second, greater than the combined flow over the American & Bridal Falls at Niagara Falls, which is 150,000 gallons per second.  The US Geological Survey (USGS) gauge at Carnegie monitored the flow, below:</span></p> </font></td> </tr> <tr> <td ALIGN="center" colspan="2"><img border="0" src="art/water_flood/graph_title.jpg" alt="USGS Gauge 03085500 at Carnegie" width="520" height="63"></td> </tr> <tr> <td ALIGN="center" colspan="2"><img border="0" src="art/water_flood/graph.gif" alt="Graph of hurricane Ivan relative to year, detailed event and history" width="580" height="400"></td> </tr> <tr> <td ALIGN="justify" colspan="2"> <p align="justify"><font SIZE="-1" FACE="arial, helvetica, sans serif"><span style="font-size:10.0pt;font-family:Arial">The graph above illustrates how Ivan relates to the normal flow of the creek.  In the course of nearly a year, Ivan and the January floods show as a sharp spike in the discharge rate while the overall discharge during the same period is also elevated relative to the norm.  A detailed weekly chart of stream depth also illustrates how rapidly the creek level rose during Ivan.  The history of records that have been kept since 1916 shows that the discharge rate during Ivan was twice that of </span><span style="font-size: 10.0pt; font-family: Arial">previous floods.</span></font></td> </tr> <tr> <td ALIGN="center" colspan="2"><img border="0" src="art/leaf_b2.gif" width="12" height="12"> <div align="center"> <table BORDER="0" width="1" CELLPADDING="5" CELLSPACING="0"> <tr> <td ALIGN="CENTER" colspan="2" width="534"> <h2 ALIGN="CENTER"><b><font face="Courier New" color="#FF8000"><a name="wooded">WOODED</a> SLOPES & NATURAL FLOODPLAIN</font></b></h2> </td> </tr> <tr> <td ALIGN="left" valign="top" width="250"> <p align="justify"><img border="0" src="art/water_flood/Wingparkbar.jpg" alt="Allegheny Land Trust's flooded Wingfield Pines floodplain" width="250" height="188"><span style="font-size:10.0pt;font-family:Arial"></o:p> </span></p> </td> <td ALIGN="right" valign="top" rowspan="2" width="272"><img border="0" src="art/water_flood/creek.jpg" alt="Chartiers Creek meanders down the Crafton-Thornburg floodplain" width="250" height="371"></td> </tr> <tr> <td ALIGN="justify" valign="top" width="250"> <p align="justify"><font size="-1" face="arial, helvetica, sans serif">Vegetation is especially important along the creek, where it filters pollutants coming into the water and slows the raging current.   Trees such as river birch, box elder and aspen stabilize creek banks naturally and are designed to re-grow from the roots after flood events. Strong trees like sycamore will not uproot easily and create shade for fish and form vital habitat and nesting sites for wetland birds such as the Great Blue Heron that depend on the fish in the creek for food. </font></p> </td> </tr> <tr> <td ALIGN="center" colspan="2" width="534"><img border="0" src="art/water_flood/panorama.jpg" alt="former golf course in Thornburg preserved as natural floodplain by municipality receives floodwaters" width="530" height="240"></td> </tr> <tr> <td ALIGN="center" colspan="2" width="534"><img border="0" src="art/water_flood/12.jpg" alt="Mickey Bannon & Sue Primm rescue 29 fish from flooded CIT ballfields on Crafton floodplain" width="530" height="348"></td> </tr> <tr> <td ALIGN="left" valign="top" width="250"><img border="0" src="art/water_flood/flood043.jpg" alt="sand bars shows ripples from recently subsided water on the flood control levee in Crafton" width="250" height="188"></td> <td ALIGN="justify" valign="top" width="272"> <p align="justify"><font SIZE="-1" FACE="arial, helvetica, sans serif">Twenty nine stranded carp were rescued from Crafton's natural floodplain, above.</font></p> <p align="justify"><font SIZE="-1" FACE="arial, helvetica, sans serif">Natural floodplains recover quickly from flood events, leaving a layer of silt or mud as the only evidence, after the water gradually subsides.  </font></p> <p align="justify"><font SIZE="-1" FACE="arial, helvetica, sans serif">While flooded, wetlands birds such as geese, duck and heron enjoy the additional habitat, feeding on stranded fish and floating on the temporary ponds.  </font></p> </td> </tr> <tr> <td ALIGN="left" valign="top" width="250"><img border="0" src="art/water_flood/flood003.jpg" alt="flooded Chartiers Creek floodplain in Crafton" width="250" height="332"></td> <td ALIGN="right" valign="top" width="272"><img border="0" src="art/water_flood/flood044.jpg" alt="watershed environmentalist John Hamm walks on silt deposited on flood control levee" width="250" height="333"></td> </tr> <tr> <td ALIGN="center" colspan="2" width="534"><img border="0" src="art/leaf_b2.gif" width="12" height="12"></td> </tr> </table> </div> </td> </tr> <tr> <td ALIGN="center" height="20" colspan="2"> <h2 ALIGN="CENTER"><b><font face="Courier New" color="#FF8000">FLOOD PHOTOS</font></b></h2> </td> </tr> <tr> <td ALIGN="center" height="20" valign="top"> <div align="center"> <table border="0" cellpadding="5" cellspacing="0" width="320" background="art/grnburl.gif" bgcolor="#006666"> <tr> <td ALIGN="center" height="40"><b><font size="-1" face="comic sans ms, arial, helvetica, sans serif"><a TARGET="wet" href="w1flood.htm">FLOOD</a></font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FF9900"> </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FF9900"> </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif"><a TARGET="wet" href="w3flood.htm">DEVELOPMENT</a></font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FF9900"> </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font size="-1" face="comic sans ms, arial, helvetica, sans serif"><font color="#FF9900"> </font><a TARGET="wet" href="w4flood.htm">BRIDGES</a> </font></b></td> </tr> <tr> <td ALIGN="center" height="27"><iframe src="w1flood.htm" width="98%" height="400" scrolling="auto" frameborder="0" name="wet"> </iframe> </td> </tr> <tr> <td ALIGN="center" height="40"><b><font size="-1" face="comic sans ms, arial, helvetica, sans serif"><a TARGET="wet" href="w1flood.htm">FLOOD</a></font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FF9900"> </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FF9900"> </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif"><a TARGET="wet" href="w3flood.htm">DEVELOPMENT</a> </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FF9900"> </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif"><a TARGET="wet" href="w4flood.htm">BRIDGES</a> <br> </font></b></td> </tr> </table> </div> </td> <td ALIGN="justify" height="20" valign="top"> <p align="justify"><font size="-1" face="arial, helvetica, sans serif"><span style="font-size: 10.0pt; font-family: Arial">Hurricane Ivan</span><span style="font-size:10.0pt;font-family:Arial">, along with the recent landslide in Killbuck Township, have highlighted the imperative need to incorporate best management practices into development.  </span></font></p> <p align="justify"><font size="-1" face="arial, helvetica, sans serif"><span style="font-size:10.0pt;font-family:Arial">Municipalities and regulatory agencies can no longer afford to ignore development practices that put our quality of life at risk, in the name of economic incentive.  It has been clearly shown that far from economic health, ignoring best management practices invites economic disaster.  </span></font></p> <p align="justify"><font size="-1" face="arial, helvetica, sans serif"><span style="font-size:10.0pt;font-family:Arial">Municipalities and regulatory agencies need to implement steep slope ordinances and adequate stormwater management plans and work with developers to insure understanding and compliance.</span></font>  </p> <p align="justify"><span style="font-size:10.0pt;font-family:Arial"><font size="-1" face="arial, helvetica, sans serif">Land use that incorporates green strategies and recognizes the value of the natural environment, particularly on steep slopes and floodplains, will curtail or forestall economic disaster.</font></span></p> <p align="justify"><font SIZE="-1" FACE="arial, helvetica, sans serif"><span style="font-size:10.0pt;font-family:Arial">Clicking on the links at left chronicle the height of Ivan's floodwaters and the aftermath.  Destruction of developed areas clearly shows the need for the mitigating effects of natural floodplains with native vegetation and riparian zones.  </span></font></p> </td> </tr> <tr> <td ALIGN="justify" valign="top" colspan="2"> <p align="justify"><font size="-1" face="arial, helvetica, sans serif"><span style="font-size:10.0pt;font-family:Arial">Bridges trapped debris, backing up water to the point where it spills over and floods our communities.  </span></font></p> <p align="justify"><font size="-1" face="arial, helvetica, sans serif"><span style="font-size: 10.0pt; font-family: Arial">Land left in its natural state, especially on steep slopes and floodplains,</span><span style="font-size:10.0pt;font-family:Arial"> prevents stormwaters from destroying our low lying communities by capturing excess water and sediment.  The economic value in the beauty of nature is an asset the residents of the Chartiers Watershed need to recognize, preserve and enhance. </span></font></td> </tr> <tr> <td ALIGN="center" colspan="2"><img border="0" src="art/leaf_b2.gif" width="12" height="12"> <p><img border="0" src="art/line.gif" width="640" height="25"></td> </tr> </center> <tr> <td ALIGN="center" colspan="2"> <div align="center"> <table BORDER="0" CELLPADDING="5" CELLSPACING="5" width="640" bgcolor="#006666" background="art/grnburl.gif"> <tr> <td ALIGN="center" colspan="2" bgcolor="#FF8000" background="art/amd/amdback.jpg"> <p align="center"><b><font size="-2" face="arial, helvetica, sans serif"><a href="amd.htm" target="lower">ABANDONED MINE DRAINAGE</a>  </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font size="-2" face="arial, helvetica, sans serif">  <a href="water_flood.htm" target="lower">FLOODS</a>  </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font size="-2" face="arial, helvetica, sans serif">  <a href="hydrology.htm" target="lower">HYDROLOGY</a>  </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font size="-2" face="arial, helvetica, sans serif">  <a href="water.htm" target="lower">WATER QUALITY<br> </a>  </font></b><font SIZE="-2" FACE="arial, helvetica, sans serif"><a href="index.html" target="_top"><br> </a></font><b><font face="arial, helvetica, sans serif" size="1"><a TARGET="main" href="WQSM.htm">WATER QUALITY & STORMWATER MANAGEMENT</a>  </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font face="arial, helvetica, sans serif" size="1"> <a HREF="LDCN.htm" TARGET="main">LAND & CONSERVATION</a>  </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font face="arial, helvetica, sans serif" size="1"> <a HREF="TRRC.htm" TARGET="main">TRAILS & RECREATION</a> <a href="sitemap.htm" target="main"><br> SITE MAP</a> </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font face="arial, helvetica, sans serif" size="1"> <a href="RIVR.htm" target="main">PLAN</a> </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font face="arial, helvetica, sans serif" size="1"> <a HREF="LINKS.htm" TARGET="main">LINKS</a> </font><font size="-1" face="comic sans ms, arial, helvetica, sans serif" color="#FFCC66">|</font><font face="arial, helvetica, sans serif" size="1"> <a href="index.html" target="_top">HOME</a> <br> </font></b></p> </td> </tr> <tr> <td ALIGN="CENTER" bgcolor="#003300" background="file:///C:/Documents%20and%20Settings/Owner/My%20Documents/My%20Projects/Webs/chartiers%20greenway/1_14_09/art/backnav2.jpg"><b><i><font face="arial, helvetica, sans serif" size="2"><font color="#FFFFCC">layout & all original material © copyright</font><font color="#FFFBDF"> </font><a HREF="mailto:rbinanth@aol.com" target="_blank"><font color="#FFCC66">ChartiersGreenway.net</font></a> <br> <font color="#00FF00"><br> </font><font color="#FFFFCC">updated 02/18/2009 <br> </font></font><font color="#FFFFCC"><br> </font></i></b><strong><img border="0" src="art/water/ccwq.gif" width="300" height="33"><font color="#FFFBDF" face="arial, helvetica, sans serif"> </font><font color="#00FF00" face="arial, helvetica, sans serif"><img src="_vti_bin/fpcount.exe/?Page=water_flood.htm|Image=2|Digits=5" alt="Hit Counter"> </font></strong></td> <td ALIGN="CENTER" valign="middle"> <div align="center"> <form action="http://www.google.com/custom" method="get" target="_blank"> <table border="0" cellpadding="0" cellspacing="0" width="159" background="art/back_leaf1.jpg"> <tr> <td colspan="2" width="204"><input maxLength="255" size="20" name="q"></td> </tr> <tr> <td width="93"><a href="http://www.google.com/webhp"><img alt="Google" src="art/google_logo.gif" align="middle" border="0" width="75" height="32"></a></td> <td width="109"><input type="submit" value="Search" name="sa"> <input type="hidden" value="GIMP:#008000;T:#000080;LW:650;BIMG:http://www.chartiersgreenway.net/art/frosty.gif;ALC:#008000;L:http://www.chartiersgreenway.net/art/iconlogo3.gif;GFNT:#808000;LC:#FF9900;LH:104;BGC:#ffffff;AH:left;VLC:#008080;S:http://www.chartiersgreenway.net;GALT:#008000;AWFID:36a2f609fa77b102;" name="cof"> <input type="hidden" value="chartiersgreenway.net" name="domains"> <input type="hidden" value="chartiersgreenway.net" name="sitesearch"></td> </tr> </table> </form> </div>  </td> </tr> </table> </div> <p align="center"> </td> </tr> </table> </div> </body>