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Parameterizing V-notch Weir Equations for Flow Monitoring in a Drainage Control Structure
Published on: April 25, 2025
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The effect of weirs on nutrient concentrations.
1Centre for Ecology & Hydrology (CEH), Maclean Building, Benson Lane, Wallingford OX10 8BB, United Kingdom.
The Science of the Total Environment
|November 8, 2015
Summary
Weir removal in the River Nidd reduced nitrate retention by up to 2.6%. This study quantified the impact of river restoration on nutrient removal, especially during low flow conditions.
Area of Science:
- Environmental Science
- River Ecology
- Water Quality Management
Background:
- River weirs alter flow dynamics and can influence nutrient cycling.
- Understanding the ecological impact of weir removal is crucial for river restoration strategies.
Purpose of the Study:
- To assess the impact of weir removal on in-stream nitrate removal in the River Nidd.
- To quantify changes in denitrification and nitrate retention following weir removal.
Main Methods:
- Utilized channel hydraulics and denitrification models.
- Incorporated river flow, water temperature, water quality, and cross-section geometry data.
- Employed counterfactual simulations to isolate weir removal effects.
Main Results:
- Weir removal reduced annual nitrate load retention by 2.6% (812 kg) in 1997 and 1.8% (382 kg) in 2000.
- The impact of weir removal on nitrate retention was most significant during low flow summer conditions.
Conclusions:
- Weir removal led to a measurable decrease in in-stream nitrate retention.
- River restoration efforts involving weir removal can alter nutrient processing dynamics.
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