1. Use of Available Information to Infer Groundwater- Surface Water Interactions - Practical Examples from BC - Practical Examples from BC Jacek Scibek M.Sc.

2. 1.BC observation well network – examples of water levels and interactions with surface water 2.Delineating areas of aquifers where GUDI wells are likely to occur 3.Aquifer heterogeneity OUTLINE:

3. Nanaimo River Nanaimo River gauge CASSIDY Obs 312 Obs 228 Obs 330 N Cassidy Aquifer (Nanaimo) Example 1:

4. Nanaimo River Obs 312 Obs 228 Obs 330

5. Obs 312 Wellfield drawdown Recovery event

6. Nanaimo River Obs 312

8. Nanaimo River Obs 312 Obs 228 Obs 330 Wells near rivers are potentially GUDI

9. Cowichan River Valley (Duncan) Example 2: 318 204 River Gauge 211 205

10. Note flow magnitude in river!!

12. Rough sketch of area of interaction of groundwater with surface water

13. Grand Forks Valley Example 3: Obs well Kettle River

15. River recharging aquifer Aquifer discharging to river Effect of aquifer heterogeneity on connection with surface water: head difference map = Aquifer Scenario 1 – Aquifer Scenario 2 (homogeneous K) (heterogeneous K) - 0.5 m + 0.5 m 0 m

16. Fraser Valley (Abbotsford) Example 4: No GUDI wells up-gradient from rivers? How far? Stream leakage?

17. Complex flow patterns (modeling results)

18. CONCLUSIONS: 1.Available information: -often not used -significance missed -objective is to avoid expensive tests done that confirm what is already known 2.BC observation well network -free source of data -most wells too close to rivers to help characterize aquifer behaviour