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The
Environment Agency measures the water quality of the river systems in England. Each is given an overall ecological status, which may be one of five levels: high, good, moderate, poor and bad. There are several components that are used to determine this, including biological status, which looks at
305:. The river flows southeast to Pondhead Copse, below which it flows through two large ponds: Brach Pond and Eeelstage Pond. It then turns east and flows under Savage Bridge and Share Lane before reaching the Nadder, northwest of Wardour.
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Also on the south bank, it is fed by a stream that has its source in Bennet's Copse near Hart Hill Stud Farm; this stream flows northeast through
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and fish. Chemical status, which compares the concentrations of various chemicals against known safe concentrations, is rated good or fail.
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The river is fed by several small waterways. On its south bank, a stream with a source near
Whitebridge Farm southeast of
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480:"Glossary (see Biological quality element; Chemical status; and Ecological status)"
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The source is
Summerleaze Pond near East Knoyle, just east of the
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is a natural waterway that flows through the ceremonial county of
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Text was copied from this source, which is available under an
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and
Billhay Pond before joining the Sem at Pondhead Copse.
459:"Hamphsire Avon Demonstration Test Catchment Project"
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360:Water quality of the River Sem in 2019:
486:. Environment Agency. 17 February 2016.
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410:25.628 km (9.895 sq mi)
281:miles (7 km) from its source near
49:Location of the mouth within Wiltshire
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713:List of civil parishes in Wiltshire
267:in England. It flows approximately
332:The underlying geology is that of
253:25.6 km (9.9 sq mi)
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887:Population of major settlements
407:7.027 km (4.366 mi)
349:the quantity and varieties of
194: • coordinates
121: • coordinates
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83:Physical characteristics
872:Parliamentary constituencies
495:Open Government Licence v3.0
233: • elevation
245:7.03 km (4.37 mi)
174: • location
101: • location
16:River in Wiltshire, England
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907:Grade II* listed buildings
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902:Grade I listed buildings
512:Catchment Data Explorer
484:Catchment Data Explorer
437:Catchment Data Explorer
237:98 m (322 ft)
216:51.045790°N 2.110142°W
668:Royal Wootton Bassett
514:. Environment Agency.
497:. © Crown copyright.
439:. Environment Agency
221:51.045790; -2.110142
973:Rivers of Wiltshire
912:Scheduled monuments
591:(cities in italics)
568:Unitary authorities
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937:Deputy Lieutenants
143:51.0737°N 2.1678°W
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351:invertebrates
344:Water quality
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952:Hill figures
810:Tetbury Avon
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745:Bristol Avon
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462:. Retrieved
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441:. Retrieved
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287:River Nadder
285:to join the
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653:Marlborough
643:Ludgershall
355:angiosperms
336:overlaying
309:Tributaries
283:East Knoyle
219: /
146: /
106:East Knoyle
735:Blackwater
695:Warminster
690:Trowbridge
648:Malmesbury
613:Chippenham
464:16 October
443:25 October
419:References
369:Ecological
250:Basin size
204:51°02′45″N
131:51°04′25″N
795:Nine Mile
709:See also:
674:Salisbury
633:Highworth
623:Cricklade
560:Wiltshire
404:Moderate
398:Moderate
387:Catchment
338:Limestone
315:Sedgehill
265:Wiltshire
261:River Sem
207:2°06′37″W
183:Wiltshire
134:2°10′04″W
110:Wiltshire
77:Wiltshire
24:River Sem
967:Category
700:Westbury
685:Tidworth
658:Melksham
638:Larkhill
598:Amesbury
390:Channel
374:Chemical
322:Sem Hill
58:Location
947:Museums
927:Schools
917:History
862:Economy
680:Swindon
628:Devizes
618:Corsham
575:Swindon
379:Overall
366:Section
328:Geology
291:Wardour
276:⁄
187:England
179:Wardour
114:England
63:Country
882:Places
855:Topics
834:Canals
815:Thames
790:Nadder
780:Kennet
760:Damson
750:Chalke
740:Bourne
723:Rivers
705:Wilton
384:Length
381:Status
376:Status
371:Status
297:Course
242:Length
168:
95:
92:Source
73:Region
892:SSSIs
825:Wylye
765:Ebble
608:Calne
508:"Sem"
433:"Sem"
401:Fail
289:near
164:Mouth
867:Flag
820:Till
755:Cole
730:Biss
663:Mere
466:2017
445:2017
395:Sem
303:A350
259:The
805:Sem
785:Key
557:of
969::
800:Og
510:.
482:.
435:.
353:,
293:.
185:,
181:,
112:,
108:,
545:e
538:t
531:v
468:.
447:.
278:4
274:1
271:+
269:4
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
