Hi, my name is Sam Townsend, and I have been a long-term volunteer for Slow The Flow for over four years.
It has been a privilege to write several guest blogs that I recommend you to view, including NFM volunteering inspired my academic research career path – Slow The Flow, which this blog will be a continuation.
Before I delve in, I would like to take the opportunity to say a huge thanks to the Trustees and volunteers of Slow The Flow for their support over the years. I was honoured to have been nominated recently for the Calderdale Community Spirit Awards, Young Community Champion Award for my charity work supporting events, such as the 2022 Climate Change Roadshow and helping with social media and comms for Slow The Flow. I would encourage anybody to get involved with a local charity or non-profit organisation, as in my experience, Slow The Flow, has significantly impacted my life both professionally and personally for the better.

Masters By Research & the Penny Eastwood Bursary
I am fortunate to have been awarded a Masters by Research (MRes) Studentship in October 2022 by the University of Huddersfield. My study investigates the influence of natural flood management (NFM) wood structures on biogeochemical processes in headwater streams at Crimsworth Dean Beck, Hardcastle Crags, with Slow The Flow and the National Trust. This is funded by the University of Huddersfield and the Penny Eastwood Bursary from Slow The Flow. My supervisory team includes my director of studies, Dr Tory Milner, Dr Ryan Wilson (both the University of Huddersfield), Dr Matthew Hill (University of Bournemouth) and Mr Bede Mullen, Slow The Flow.
Penny Eastwood/Dongria Kondh was an environmental activist and founder of Treesponsibility. Prior to, and following the Boxing Day Floods in 2015, Dongria was a huge advocate for promoting natural defences by tree planting and constructing leaky woody dams to help “Slow the Flow.” After her passing, a bursary was created and funded by Calderdale Council, the Environment Agency, the National Trust and Slow The Flow to help students researching natural flood management. You can learn more information here: New bursary announced to help students researching natural flood management – Slow The Flow
I am lucky to be the second recipient of this bursary with Sophie Tankard being the first awardee. Sophie is now a Water Engineer at WSP, an engineering consultancy. You can read more about her experience as a Masters student here: The Penny Eastwood Bursary – Sophie’s Blog – Slow The Flow.

My Research Project – Background and Rationale
Current climate predictions suggest that flood events will increase in intensity and frequency, whilst weather patterns and seasonality become increasingly unpredictable due to the increase in global average temperature changes (1).
In partnership with the National Trust at Hardcastle Crags, since 2016, Slow The Flow volunteers have installed over 800 in-channel and strategically placed (along the contour) leaky woody dams (LWDs), which increase hydraulic roughness, and interception rates (2; 3). Furthermore, Slow The Flow envisions helping to mitigate flooding in Hebden Bridge and the Calder valley whilst improving ecological conditions in the headwaters of the River Calder (3). Once the woody debris decomposes, it provides a temporary habitat and food source for terrestrial and aquatic fauna and flora (3; 4).
LWDs primary role is to increase water attenuation, often in headwater streams. Previous research has focused on the hydrological impacts and the flood mitigation effects of LWDs (5). Less research has examined the effect of LWDs on improving water quality. This topic is an underdeveloped area of research that requires further exploration of the direct, and indirect impact of LWDs have on biogeochemical processes in ephemeral streams (6; 7). Biogeochemical processes play a critical role in riverine ecosystems, influencing biogenic nutrients; for example, phosphates, nitrates, and dissolved oxygen in the water column and bed sediments, and carbon storage (8-10).
As a result, I hope to contribute more data evidence that LWDs not only help slow the flow of water during a flood event, but can potentially act as a filter for harmful biogenic nutrients in large quantities and help store carbon: i.e. they can mitigate against the causes as well as effects of climate change (6).
Fieldwork
The highlight of my Masters so far has been the fieldwork. For my first fieldwork campaign, I spent 3 weeks in Hardcastle Crags gathering water and sediment samples during medium-high discharge. I have strategically selected sites to gather a representative sample (given my 1 year time frame) which would demonstrate the impact NFM wood structures have on water quality.
The Crimsworth Dean wood area, where some of these dams where first constructed 6 years ago, had a combination of different types of leaky woody dams and most importantly, a control stream which could be used as a direct comparison. In addition, upstream is an agricultural area, where open bodies of water and streams enter the wood. Also, downstream of Crimsworth Dean wood, I am able to observe Crimsworth Dean Beck, a tributary of the Hebden Water (which flows into the River Calder) to gather a broader understanding of how Crimsworth Dean catchment works.


Laboratory Work
For the water quality analysis, phosphate and nitrate needed to be analysed immediately (within 48 hours) after the sample was taken. Therefore, the day after fieldwork the samples were filtered (a ‘total suspend solids’ – the amount of organic material suspended in the water column, was performed at the same time). The remaining water samples are stored at pH 2 (acid state) for an elemental analysis; calcium, phosphorus and iron were analysed using an Ignition Coupling Plasma Optical Emission Spectroscopy (ICP-OES).
For the sediment analysis, several techniques were used, including loss on drying, testing sediment moisture, loss on ignition, testing particulate organic matter; nitrate and phosphate analysis of the soils.

Progress to date, what are my thoughts for the future?
At the time of writing (January 2023), I haven’t completed any data analysis or discussion, so don’t want to jump to any conclusions. However, I look forward to sharing my learnings and findings in a future blog, when I will be on the “next step” of my academic career and sharing the outcome of my MRes thesis.
1 Ogunbode, C. A., Böhm, G., Capstick, S. B., Demski, C., Spence, A., & Tausch, N. (2019). The resilience paradox: flooding experience, coping and climate change mitigation intentions. Climate Policy, 19(6), 703-715. https://doi.org/10.1080/14693062.2018.1560242
2 Slow The Flow Calderdale. (2022). About us. Retrieved from https://slowtheflow.net/about-us-2/ [Accessed 03/11/22]
3 Slow The Flow Calderdale. (2022). Woodland Management Position Statement. Retrieved from https://slowtheflow.net/woodland-management-position-statement/ [Accessed 03/11/22]
4 National Trust. (2016). Hardcastle Crags Woodland Management Plan April 2017- March 2027. https://forestplans.co.uk/uploads/attachment/216/summary-management-plan.pdfw
5 Lane, S. N. (2017). Natural flood management. WIREs Water, 4(3), e1211. https://doi.org/10.1002/wat2.1211
6 Lo, H. W., Smith, M., Klaar, M., & Woulds, C. (2021). Potential secondary effects of in‐stream wood structures installed for natural flood management: A conceptual model. WIREs Water, 8(5). https://doi.org/10.1002/wat2.1546
7 Gómez-Gener, L., Siebers, A. R., Arce, M. I., Arnon, S., Bernal, S., Bolpagni, R., Datry, T., Gionchetta, G., Grossart, H.-P., Mendoza-Lera, C., Pohl, V., Risse-Buhl, U., Shumilova, O., Tzoraki, O., von Schiller, D., Weigand, A., Weigelhofer, G., Zak, D., & Zoppini, A. (2021, 2021/09/01/). Towards an improved understanding of biogeochemical processes across surface-groundwater interactions in intermittent rivers and ephemeral streams. Earth-Science Reviews, 220, 103724. https://doi.org/https://doi.org/10.1016/j.earscirev.2021.103724
8 Shil’krot, G. S., & Yasinskii, S. V. (2002, 2002/05/01). Spatial and Temporal Variability of Biogenic Elements Flow and Water Quality in a Small River. Water Resources, 29(3), 312-318. https://doi.org/10.1023/A:1015684430845
9 Alexander, R. B., Böhlke, J. K., Boyer, E. W., David, M. B., Harvey, J. W., Mulholland, P. J., Seitzinger, S. P., Tobias, C. R., Tonitto, C., & Wollheim, W. M. (2009). Dynamic modeling of nitrogen losses in river networks unravels the coupled effects of hydrological and biogeochemical processes. Biogeochemistry, 93(1-2), 91-116. https://doi.org/10.1007/s10533-008-9274-8
10 Wohl, E., Lininger, K. B., & Scott, D. N. (2018). River beads as a conceptual framework for building carbon storage and resilience to extreme climate events into river management. Biogeochemistry, 141(3), 365-383. https://doi.org/10.1007/s10533-017-0397-7