WebMar 24, 2024 · 5 litres(l) second(s) / hectare (Ha) This means that if your site is 1,000m2 (or 0.1ha) then the runoff rate for your site is 5 x 0.1 = 0.5 l/s. The greenfield runoff rate is … Webdisposal of surface water runoff. Greenfield runoff rates Default Edited Q (l/s): 1.98 1.98 1 in 1 year (l/s): 1.64 1.64 1 in 30 years (l/s): 3.96 3.96 1 in 100 year (l/s): 5.09 5.09 1 in …
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WebAccording to CIRIA 609 (CIRIA, 2004) common values used for greenfield runoff rates vary between 5 to 7 l/s/ha. However, care should be taken if applying these values, as they … Webaccept 5l/s/ha as a minimum discharge rate without thorough justification. Attenuation. To meet greenfield discharge rates, water needs to be stored/attenuated so it can be … sonic 3 air modgen edition
Comment on estimation of Greenfield Runoff Rates - ResearchGate
WebSep 8, 2024 · Max Allowable Volume Calculation Method - The runoff volume from the site is calculated in the following manner. Calculate the total rainfall for the storm details specified (6 hour, 100 year return period by default). Calculate the PR as defined below (this is the same as the unit hydrograph method. WebAs detailed in section 2.2, Southwark expect the existing brownfield/ greenfield runoff rates for development sites to be calculated as part of the drainage strategy. This section details the requirements for calculating the runoff rates and selecting a suitable proposed runoff rate for the design. Web14. The standard for SUDS is to reduce peak flow rates and volumes to greenfield levels for critical rain storms. This can generally be taken to be a 1 in 100 yr 6 hour storm. Modelling was undertaken for Ashford Borough Council‟s Local Development Framework which estimates a brownfield runoff rate for this critical storm as roughly 36 l/ha/s. sonic 3 air mod game