Response of algae to sewer misconnections

Dave Chandler, Prof. David Lerner, Prof. Philip Warren, Prof. Lorraine Maltbyd.chandler@sheffield.ac.uk@diatomdave

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Why are algae important

• Primary producers• Oxygen provision• Carbon fixing• Nutrient retention• Metal retention

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Representative substances in misconnection effluent

UKWIR (2012)

36%

36%

7%

7%

7%6% 2%

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Representative substances in misconnection effluent

UKWIR (2012)

• Majority discharge soaps/detergents

36%

36%

7%

7%

7%6% 2%

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Representative substances in misconnection effluent

UKWIR (2012)

• Majority discharge soaps/detergents

• Washing machines make up approx. 1/3 36%

36%

7%

7%

7%6% 2%

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Experimental design

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Experimental design• Collect algae from rivers

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Experimental design• Collect algae from rivers

• Grow algal communities on tiles

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Experimental design• Collect algae from rivers

• Grow algal communities on tiles

• Produce artificial washing machine effluents

18/04/23 © The University of Sheffield

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Experimental design• Collect algae from rivers

• Grow algal communities on tiles

• Produce artificial washing machine effluents

• Expose algal to effluents at different concentrations

Experimental concept

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Control0% effluent

A0.1% effluent

B1% effluent

C10% effluent

D50% effluent

Phosphorus containing detergent

Phosphorus free detergent

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Chlorophyll a results

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Chlorophyll a results

Ch

loro

ph

yll

a

con

cen

trati

on

(mg/c

m2)

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Chlorophyll a results

Ch

loro

ph

yll

a

con

cen

trati

on

(mg/c

m2)

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Chlorophyll a results

Ch

loro

ph

yll

a

con

cen

trati

on

(mg/c

m2)

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Conclusions

• Detergent pollution reduces algal abundance

• Different detergents produce similar responses

• Follow up work• Investigate changes in algal community structure

• Investigate impacts of misconnections in the field

• Expand to other groups of organisms

d.chandler@sheffield.ac.uk

@diatomdave