A trial to extend the Riverfly Partnership monitoring initiative to measure flow and sediment impacts.

1. Extending riverflyExtending riverfly
monitoringmonitoring
Richard Chadd,Richard Chadd,
Senior EnvironmentalSenior Environmental
Monitoring Officer,Monitoring Officer,
Environment AgencyEnvironment Agency
(Lincolnshire and(Lincolnshire and
Northamptonshire Area)Northamptonshire Area)

2. The old approach – water qualityThe old approach – water quality
• Started in the 1960sStarted in the 1960s
• From 1990 onwards,From 1990 onwards,
regular reporting toregular reporting to
government (‘colours ongovernment (‘colours on
maps’), NRA then EAmaps’), NRA then EA
• 1995 – 2005: General1995 – 2005: General
Quality AssessmentQuality Assessment
(GQA)(GQA)
• Trend very muchTrend very much
upward, so now ratherupward, so now rather
old newsold news

3. Different stressesDifferent stresses
• Drought & abstractionDrought & abstraction
pressurepressure
• Leads to development ofLeads to development of
Lotic-invertebrate Index forLotic-invertebrate Index for
Flow Evaluation (LIFE) in 1999Flow Evaluation (LIFE) in 1999
• British invertebrates placedBritish invertebrates placed
in one of six flow-groupsin one of six flow-groups
based on velocity preferencebased on velocity preference
• Final index is derived fromFinal index is derived from
taxa in these groups &taxa in these groups &
adjusted by relativeadjusted by relative
abundanceabundance

4. Different stresses (2)Different stresses (2)
• Sediment accumulation (tillage,Sediment accumulation (tillage,
livestock poaching, urbanlivestock poaching, urban
runoff)runoff)
• Metric for this - Proportion ofMetric for this - Proportion of
Sediment-sensitiveSediment-sensitive
Invertebrates (PSI)Invertebrates (PSI)
• Derives an abundance-Derives an abundance-
weighted ratio of sediment-weighted ratio of sediment-
sensitive to sediment-tolerantsensitive to sediment-tolerant
taxa (output = 0 to 100)taxa (output = 0 to 100)
• EU Water Framework DirectiveEU Water Framework Directive
will require other stressors towill require other stressors to
be assessed and classifiedbe assessed and classified

5. HydroEcological Validation (HEV): RiverHydroEcological Validation (HEV): River
Nene (Duston Mill, NorthamptonNene (Duston Mill, Northampton))

7. Score reduces withScore reduces with
rising abundance ofrising abundance of
fine sediment & lowfine sediment & low
flow indicators andflow indicators and
rises with sedimentrises with sediment
& flow-sensitive& flow-sensitive
taxa.taxa.
May try 1, -1, -2, -3,May try 1, -1, -2, -3,
as presence of theseas presence of these
indicators in lowindicators in low
abundance indicatesabundance indicates
a ‘healthy’ state.a ‘healthy’ state.
Original 8-taxon listOriginal 8-taxon list
still operates.still operates.