Added Rainfall and river flow: 23 to 29 August report. New report: Rainfall and river flow: 7 to 13 March 2018. New report published: Rainfall and river flow: 29 August to 4 September 2018. New report published: Rainfall and river flow, 19 to 25 September 2018. Added rainfall and river flow summary for 9 to 15 December 2020. Flow occurs as a consequence of gravity and the slope of the conduit. Added Rainfall and river flow summary for 19 to 25 August 2020. New report published: Rainfall and river flow, 10 to 16 October 2018. The cross-sectional area of a full circular pipe can be determined as follows: A = π * (Diameter) 2 / 4. New report published: Rainfall and river flow: 15 to 21 August 2018. We have published the rainfall and river flow summary for 22 to 28 January 2020. We've published the rainfall and river flow summary for 10 to 16 July 2019. 2. New report: Rainfall and river flow: 21 to 27 March 2018. We've published the rainfall and river flow summary for 4 to 10 December 2019. Then when the river flow rate drops you may find yourself carrying your boat over the rocks. We've published the rainfall and river flow summary for 9 to 15 October 2019. Readings are transferred via telemetry to internal and external systems in, or close to real time. If you look at 100% exceedence, it is 0.25 m 3 /s, which is the lowest flow rate recorded, so by definition the flow in the river is at this flow rate or more for 100% of the time. New report published: Rainfall and river flow, 11 to 17 April 2018. The easiest way to get a fairly accurate measure of your water flow rate is to time yourself filling up a bucket. New report: Rainfall and river flow, 14 to 20 February 2018. This dataset covers monitoring data that is only updated on our systems on a daily update cycle. New report published: Rainfall and river flow, 16 to 22 January 2019. New report published: Rainfall and river flow, 5 to 11 June 2019. Some hydrometric flow data may also be available from commercial water companies for privately operated channels and water resources installations. It is one of the longest rivers in the world covering a distance of 4,132 miles. New report published: Rainfall and river flow, 7 to 13 August 2019. We use cookies to collect information about how you use GOV.UK. The Gauged Daily Flow is the mean river flow in cubic metres per second (abbreviated to m 3 s-1 and sometimes also referred to as 'cumecs') in a water-day, (09.00 to 09.00 G.M.T.) We have published the rainfall and river flow summary for 17 to 23 June 2020. Added Rainfall and river flow: 5 to 11 July report. Added Rainfall and river flow: 31 May to 6 June report. Added Rainfall and river flow summary for 5 to 11 August 2020. So please use the information in the table below to help you plan your safe day on the river. Note that measured height ‘h’ must be given in metres. The rate at which a liquid flows will vary according to area of the pipe or channel through which it is passing and the velocity of the liquid. Flow patterns in many rivers have been significantly altered and will not return to natural flow regimes. Added rainfall and river flow summary 19 to 25 April. We've published the rainfall and river flow summary for 23 to 29 October 2019. We've published the rainfall and river flow summary for 25 September to 1 October 2019. New report added: Rainfall and river flow, 30 January to 5 February 2019. River flow data held on the NRFA originate from gauging stations operated by a range of Measuring Authorities. The NRFA collates records of the daily mean flow (otherwise known as, Gauged Daily Flows). Hydrological Summary for November 2020 published, Training Course - Hydrometry: River Discharge Monitoring using ADCPs, Hydrological Summary for October 2020 published.