new flow monitoring station

In 2019 we witnessed Walley Creek go dry (subsurface) at the Shores Drive bridge.  Losing water in a creek that supports so much life was heartbreaking, and we reached out to Provincial hydrologists for help understanding what was going on.  While we suspected that upgrades to the RDN GNPCC had something to do with it, the experience made us want to better understand the hydrology of Walley Creek. 

In August 2019 Provincial hydrologist Neil Goeller installed a flume near the mouth of the creek, with permission from the landowner. Another flume was installed where Walley Creek flows past the GNPCC.  At both sites level loggers (transducers) and trail cameras were also installed.  During low flow we collected water level data using a ruler, and in high flows a Flow Tracker was used to measure discharge.  Data from the level logger (transducer) and photos were downloaded regularly.   

The trail cameras recorded what we'd observed, that when it rains the stream channel can go from empty to full in less than an hour.  The photos above are from the lower flow monitoring station on September 12, 2019, between 1:45 - 2:00pm.

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During rain storms the flumes were quickly overwhelmed, making them ineffective at flow monitoring.  The lower flume was removed, and the upper one left in place to measure flow in drier seasons. 

During the summer of 2021 Walley Creek was often subsurface, with only isolated pools, from the GNPCC all the way down to Hammond Bay.  But then, a number of times we noticed a lot of water suddenly flowing, even when there had not been any rainfall in previous days/ hours.  We tracked it back to a storm water outfall on the GNPCC property.  We were told that the new digesters have a perimeter drain – could these be affecting the creek's base flows during the summer?  Where does ground water from around the GNPCC go, if not into the creek?

​For complicated reasons, the data that has been collected since 2019 isn't useful in establishing a flow rating curve.   Neil explained in 2020 that the Flow Tracker measurements had a percent Q close to 10% in some panels, when it should ideally be <5%.  Also, there was a high standard of error for velocity, which can be a function of turbulence.  He suggested moving the monitoring station slightly upstream to a flatter location, and making sure the flow isn't impeded by our feet, or branches or debris, to get more accurate measurements. 

In August 2023, we were welcomed into the BCCF Flo Mo, or flow monitoring network. This summer (August 2024), BCCF and Provincial hydrologists supported us to install a new flow monitoring station slightly upstream of the old one.  The BCCF also offered to help apply for funding to purchase a Flow Tracker so that our group and others can take the required minimum 6 flow measurements a year.  Right now we're sharing a Flow Tracker on loan from the Province with several other groups.  We'll continue to download the transducer data and trail camera photos, as well as take flow measurements.  BCCF has created data sheets to formalize what happens at each site visit, and we'll get a Provincial hydrometric station number.​

We're hopeful going forward that this relationship with BCCF will bring our data up to Resources Information Standards Committee (RISC) grade "C" standards and allow us to have an accurate understanding of the flows on Walley Creek.  We want to understand what consistent flows look like, what the expected peak flows are, and in what conditions the creek ceases to flow continuously. 
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Walley Creek has been drained, moved, and channeled. It experiences illegal dumping, competition from invasive plants, and toxic road runoff, and it's still so beautiful and supports rich biodiversity.  Understanding high and low flows on this creek will be key to our efforts to mitigate anthropogenic effects and enhance the health of the watershed.