Editing Bath, Somerset (section)

===Physical geography===
Bath is in the Avon Valley and is surrounded by limestone hills as it is near the southern edge of the [[Cotswolds]], a designated [[Area of Outstanding Natural Beauty]], and the [[Mendip Hills]] rise around {{convert|7|miles}} south of the city. The hills that surround and make up the city have a maximum altitude of {{convert|781|ft|0|abbr=off}} on the Lansdown plateau. Bath has an area of {{convert|11|mi2|0|abbr=off}}.<ref>{{cite web |url=http://www.bathnes.gov.uk/environmentandplanning/Pollution/contaminatedland/Pages/default2.aspx |title=Published Contaminated Land Inspection of the area surrounding Bath |publisher=Bath and North East Somerset Council |access-date=25 January 2011 |archive-url=https://web.archive.org/web/20120513102611/http://www.bathnes.gov.uk/environmentandplanning/Pollution/contaminatedland/Pages/default2.aspx |archive-date=13 May 2012 }}</ref>
[[File:Clevelandhouse.JPG|thumb|alt=A iron bridge spanning water. In the background is a yellow stone building. On the left trees reach out over the water.|right|Cleveland House and the cast iron bridges of [[Sydney Gardens]] over the [[Kennet and Avon Canal]]]]

The [[floodplain]] of the Avon has an altitude of about {{cvt|59|ft|0}} above sea level,<ref>{{cite web |url=http://idox.bathnes.gov.uk/WAM/doc/BackGround%20Papers-92552.pdf?extension=.pdf&id=92552&location=VOLUME1&contentType=application/pdf&pageCount=1 |title=Bath Western Riverside Outline Planning Application Design Statement, April 2006, Section 2.0, Site Analysis |date=April 2006 |access-date=2 May 2015 |url-status=dead |archive-url=https://web.archive.org/web/20160810063821/http://idox.bathnes.gov.uk/WAM/doc/BackGround%20Papers-92552.pdf?extension=.pdf&id=92552&location=VOLUME1&contentType=application%2Fpdf&pageCount=1 |archive-date=10 August 2016 }}</ref> although the city centre is at an elevation of around {{convert|25|m|ft}} above sea level.<ref>[[Ordnance Survey]] mapping</ref> The river, once an unnavigable series of [[braided streams]] broken up by [[swamp]]s and ponds, has been managed by [[weir]]s into a single channel. Periodic flooding, which shortened the life of many buildings in the lowest part of the city, was normal until major flood control works were completed in the 1970s.<ref>{{cite web |title=Carr's Mill, Lower Bristol Road, Bath Flood Risk Assessment |url=http://idox.bathnes.gov.uk/WAM/doc/BackGround%20Papers-212576.pdf?extension=.pdf&id=212576&location=VOLUME1&contentType=application/pdf&pageCount=1 |publisher=Bath and North East Somerset |access-date=17 September 2010 |url-status=dead |archive-url=https://web.archive.org/web/20110722034626/http://idox.bathnes.gov.uk/WAM/doc/BackGround%20Papers-212576.pdf?extension=.pdf&id=212576&location=VOLUME1&contentType=application%2Fpdf&pageCount=1 |archive-date=22 July 2011 }}</ref> Kensington Meadows is an area of mixed woodland and open meadow next to the river which has been designated as a [[local nature reserve]].<ref>{{cite web |title=Kensington Meadows |url=http://www.lnr.naturalengland.org.uk/Special/lnr/lnr_details.asp?C=35&N=&ID=984 |publisher=Natural England |access-date=23 August 2015 |url-status=dead |archive-url=https://web.archive.org/web/20160304074101/http://www.lnr.naturalengland.org.uk/Special/lnr/lnr_details.asp?C=35&N=&ID=984 |archive-date=4 March 2016 }}</ref>

Water bubbling up from the ground as [[List of geothermal springs in the United Kingdom|geothermal springs]] originates as rain on the [[Mendip Hills]]. The rain percolates through limestone aquifers to a depth of between {{cvt|9000|to|14000|ft|-2}} where geothermal energy raises the water's temperature to between 64 and 96&nbsp;°C (approximately 147–205&nbsp;°F). Under pressure, the heated water rises to the surface along fissures and faults in the limestone. Hot water at a temperature of {{convert|46|°C|°F|0}} rises here at the rate of {{convert|1170000|L|impgal|0}} daily,<ref>{{cite web |url=http://www.romanbaths.co.uk/index.cfm?fuseAction=SM.nav&UUID=F9F320C4-1A95-4C04-AC609094E5B5DFD3 |title=Sacred Spring |access-date=31 October 2007 |publisher=Roman Baths Museum Web Site |archive-url=https://web.archive.org/web/20071102122621/http://romanbaths.co.uk/index.cfm?fuseAction=SM.nav&UUID=F9F320C4-1A95-4C04-AC609094E5B5DFD3 |archive-date=2 November 2007 |url-status=dead }}</ref> from the Pennyquick [[geological fault]].

In 1983, a new spa-water bore-hole was sunk, providing a clean and safe supply for drinking in the Pump Room.<ref>{{cite web |url=http://www.romanbaths.co.uk/walkthroughs/spa-water-fountain |title=Hot Water |access-date=31 October 2007 |publisher=Roman Baths Museum Web Site |archive-url=https://web.archive.org/web/20141228065838/http://www.romanbaths.co.uk/walkthroughs/spa-water-fountain |archive-date=28 December 2014 |url-status=live }}</ref> There is no universal definition to distinguish a [[hot spring]] from a [[Geothermal gradient|geothermal]] spring, although, by several [[Hot spring#Definitions|definitions]], the Bath springs can be considered the only hot springs in the UK. Three of the springs feed the thermal baths.<ref>{{cite web |title=The Hot Springs of Bath: Geology, geochemistry, geophysics |url=https://www.thermaebathspa.com/the-spa/natural-thermal-waters/ |format=PDF |publisher=Bath and North East Somerset |access-date=26 August 2012 |archive-url=https://web.archive.org/web/20140113025346/http://www.thermaebathspa.com/the-spa/natural-thermal-waters/ |archive-date=13 January 2014 |url-status=live }}</ref>