Welshpool PAS

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" colspan=3 height=55 BGCOLOR="#FFFFFF" TEXT="#080000"> <div> <FONT SIZE="6" COLOR="#BBBBBB" FACE="Arial" >Welshpool PAS      </FONT><A HREF="index.htm" TARGET="_top" TITLE=" Edenvale Young Associates Ltd "><U>Home </U></A> <FONT SIZE="6" COLOR="#BBBBBB" FACE="Arial" > </FONT>   |     <A HREF="id86.htm" TARGET="_top" TITLE=" Welcome"><U>Site Centra</U></A>l    |     <A HREF="id46.htm" TARGET="_top" TITLE="News Desk ......"><U>News </U></A>     |       <A HREF="id96.htm" TARGET="_top" TITLE="People ......"><U>People</U></A>      |      <A HREF="id95.htm" TARGET="_top" TITLE="Civil Design ......"><U>Design</U></A>      |     <A HREF="id94.htm" TARGET="_top" TITLE="Software Computing ......"><U>Computing</U></A>     |       <A HREF="id78.htm" TARGET="_top" TITLE="Knighton PAS"><U>Projects</U></A><FONT SIZE="6" COLOR="#BBBBBB" FACE="Arial" > </FONT></div> </td> </tr><tr> <td valign="top" rowspan="2" width=200 BGCOLOR="#FFFFFF" TEXT="#080000"> <bR> <div> P<FONT SIZE="4" COLOR="#0000FF" FACE="Arial" >roject links</FONT></div> <div> <A HREF="id66.htm" TARGET="_top" TITLE="Project Descriptions"><U>Home</U></A></div> <div> <A HREF="id55.htm" TARGET="_top" TITLE="Marine water quality"><U>Previous</U></A></div> <div> <A HREF="id78.htm" TARGET="_top" TITLE="Knighton PAS"><U>Next</U></A></div> <div> <A HREF="id102.htm" TARGET="_top" TITLE="John Young ......"><U>Return to cv</U></A></div> </td> <td valign="top" height=393 colspan=2 BGCOLOR="#FFFBF0" TEXT="#080000"> <bR> <div> <TABLE BORDER="0" CELLPADDING="2" CELLSPACING="1" WIDTH="582" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="VOID" RULES="NONE" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 282 ><NOBR><div> W<FONT SIZE="5" COLOR="#0000FF" FACE="Arial" >elshpool flooding </FONT></div> <div> project appraisal study<FONT SIZE="4" COLOR="#0000FF" FACE="Arial" ><B>.</B></FONT></div> <bR> <div> <B>Keywords</B></div> <div> Flooding and Flood Risk Assessment</div> <div> Economic, Environmental and Social Appraisal</div> <div> Condition Survey</div> <div> FEH ISIS TUFLOW</div> <bR> <div> <B>Client, Architect & Other Organisations</B></div> <div> Powys County Council </div> <div> Eden Vale Modelling Services</div> <div> The Welsh Assembly Government </div> </NOBR></tD> <tD VALIGN=TOP><NOBR><bR> <div> <IMG SRC="28e13f20.jpg" border=0 width="275" height="242" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <div> <I>Flooding in July 1968</I></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 539 WIDTH="287"><div> <B>Description</B></div> <div> Unnoticed by many the Lledan Brook runs  through the centre of Welshpool.  In common with many other urban rivers the brook has been gradually covered and culverted to accommodate residential and commercial development in the centre of the town. Houses, shops, the mill, library, livestock market and roads have all been built over or directly adjacent to the culvert. </div> <bR> <div> This process has extended through several centuries and has seen considerable change to the nature of the river. Today only 200m of open watercourse remains with approximately 1.1 km flowing below the town in culvert.  There is no visible evidence of the brook in Brook Street. To a large extent the watercourse has been lost and forgotten.  The brook is now only recognised as a flooding problem.</div> <bR> <div> The Lledan Brook is classified as a critical ordinary watercourse and the Environment Agency has identified over 272 properties at risk of flooding. In July 1968 there was extensive summer flooding   throughout the town. Recent flooding in 1998 and 2000 has been attributed to a blocked trash screen on the Ceunant Book, Bron-y-Buckley and in the culvert. </div> <bR> <bR> <bR> <bR> <bR> </tD> <tD VALIGN=TOP WIDTH="284"><div> <B>Scope of Work</B></div> <div> Following the preparation and submission of the pre-feasibility study in 2002 Powys County Council were given grant funding to undertake a full project appraisal to consider the issue of flooding in Welshpool.  The nature and age of the culvert required a careful programme of work. Work is currently being undertaken on the project appraisal and includes:</div> <bR> <div> <IMG BORDER="0" SRC="Symb075c00b700c800000000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Diving survey of the culvert which is approximately 1.1km long with a cross section of 2.5m x 1.2m high in places.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800000000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Condition assessment of the culvert</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800000000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">Topographic survey of the Lledan Brook</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800000000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">The development of a hydrological model to assess the flow of water in the culvert.</div> <div> <IMG BORDER="0" SRC="Symb075c00b700c800000000.png" HEIGHT="13" WIDTH="24" ALIGN="bottom" HSPACE="0" VSPACE="0">A hydraulic model of the culvert system using <FONT SIZE="2" COLOR="#0000FF" FACE="Arial" ><A HREF="id94.htm" TARGET="_top" TITLE="Software Computing ......"><U>ISIS and Tuflow</U></A></FONT><A HREF="id94.htm" TARGET="_top" TITLE="Software Computing ......"><U>.</U></A></div> <bR> <div> <FONT SIZE="2" COLOR="#000000" FACE="Arial" >In order to assess the extent of flooding in the urban area a combined </FONT>ISIS and Tuflow t<FONT SIZE="2" COLOR="#000000" FACE="Arial" >wo dimensional model was constructed to analyse flood damages within the town for a range of return periods and to assess the potential for flood alleviation works. Interviews have also been held with local residents.</FONT></div> <bR> </tD> </tR> </TABLE></div> <bR> </td> </tr><tr> <td valign="top" colspan=2 height=32 BGCOLOR="#FFFBF0" TEXT="#080000"> <div> <A HREF="id78.htm" TARGET="_top" TITLE="Knighton PAS"><U><B><IMG SRC="0111b180.jpg" border=0 width="27" height="24" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></U></A><B>  </B><A HREF="id55.htm" TARGET="_top" TITLE="Marine water quality"><U><B><IMG SRC="0121e160.jpg" border=0 width="30" height="22" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></B></U></A><B>  </B><IMG BORDER="0" SRC="1x1.gif" HEIGHT="23" ALIGN="BOTTOM" HSPACE="0" VSPACE="0" WIDTH="27"><B>  </B><IMG BORDER="0" SRC="1x1.gif" HEIGHT="22" ALIGN="BOTTOM" HSPACE="0" VSPACE="0" WIDTH="27"></div> <bR> </td> </tr></table></body>