1. (Edinburgh-associated) Research Team Dr. Steve Wallis & Catherine Morgan (PhD student) (Heriot Watt University) Dr. Kate Heal & Alan Jones (PhD student) (The University of Edinburgh) Dr. Rebecca Lunn & PhD student? (University of Strathclyde)

2. Flow and quality issues in SUDS ponds Combination of modelling (HWU & SU) and field sampling (EU)

3. Flow attenuation and dilution in SUDS ponds: Research questions How are flow attenuation and solute dilution related to available storage and outlet configuration? Mathematical modelling results for pond with v- notch weir at 2m above pond base and various submerged pipes: 4 diameters 4 elevations

4. Relationship between peak flow attenuation, storage and outlet configuration; legend - pipe diameter; dashed lines – pipe elevation Increasing peak flow attenuation 0.5m 0m 1.0m 1.5m Anomalies Flow attenuation results

5. Summary of key issues: Peak flow attenuation increases as pipe elevation decreases (more storage available) Peak flow attenuation increases as pipe diameter increases (less storage used) Two regimes: weir used – normal weir not used - anomolous Flow attenuation results

6. Improving water quality 0m 0.5m 1.0m 1.5m Relationship between peak solute dilution, storage and outlet configuration; legend - pipe diameter; dashed lines – pipe elevation First flush dilution results

7. Summary of key issues: Peak solute dilution increases as pipe elevation increases (more dilution volume available) Peak solute dilution increases as pipe diameter decreases (more dilution volume available) First flush dilution results Conclusion: Conflict between flow attenuation and solute dilution

8. Sediment in SUDS ponds: Research questions Characterise sediment accumulation and quality in SUDS ponds Investigate sediment particle size- metal concentration relationships Model sedimentation patterns (and quality?) in SUDS ponds Provide recommendations for design and maintenance of SUDS ponds Effect of loss of storage on performance of pond Halbeath Pond Sediment in Pond 7

9. Sedimentation patterns and accumulation rates Effect of surface water management train on sedimentation rate: –1.0 cm a -1 in Halbeath Pond (no management train) –0.4 cm a -1 in Linburn Pond (management train) 1999 2003 Main inflow Linburn Pond 2003

10. Sediment quality results Sediment quality “hotspots” in ponds, normally close to inlet. So far mean concentrations of potentially toxic metals, N, P and hydrocarbons in Dunfermline pond sediments do not exceed sediment quality guidelines (e.g. Ontario Ministry of Environment Severe Effect Levels), apart from Ni and Cr in Pond 7. Mean concentrations close to guideline values for Ni and Cr in all ponds. Increased metal concentrations over time

11. Current work SUDS pond sediment modelling (advection, mixing, settling) Risk assessment of SUDS pond sediments according to land use Apply geomorphological principles to model sediment accumulation in SUDS ponds Use geophysical methods to survey sediment depths in SUDS ponds Post-processed 450 MHz ground penetrating radar trace of transect across the Wetland Water Sediment Depth (m) 1.0 m 0.3 m 0.5 m 0.7 m