• A - watershed area
  • AB - total allowable drainage area to buffer
  • AC - natural area conserved
  • AD - area disconnected
  • Ar - filter bed area
  • As - surface area, sedimentation basin
  • BMPRE - BMP removal efficiency for total phosphorus
  • C - flow–weighted mean concentration of the pollutant in urban runoff
  • Ca - calcium
  • CaCl2 - calcium chloride
  • Cl - chloride
  • CMA - calcium magnesium acetate
  • Vcp-ED - extended detention of the 1–year post–development runoff
  • Cu - copper
  • DA - % Served fraction of the drainage area served by the BMP
  • df - depth of filter bed
  • fcsoil - infiltration rate
  • FCN - free cyanide
  • Fe - iron
  • hf - head above filter bed
  • Hg - mercury
  • I - impervious cover
  • Ia - initial abstraction
  • IC - percent new impervious cover
  • Ipost - post–development site imperviousness
  • K - coefficient of permeability
  • KAc - potassium acetate
  • KFo - potassium formate
  • L - pollutant loading
  • Lpost - average annual load of total phosphorus exported from the post–development site
  • Lpre - average annual load of total phosphorus exported from the site prior to development
  • LR - annual total phosphorus load removed by the proposed BMP
  • Mg - magnesium
  • MgCl2 - magnesium chloride
  • N - nitrogen
  • Na - sodium
  • NaCl - sodium chloride
  • NH3 - ammonium
  • NOx - nitrogen oxides
  • P - precipitation depth
  • P - phosphorus
  • Pj - fraction of rainfall events that produce runoff
  • Qf - extreme flood storage volume
  • Qi - peak inflow discharge
  • Qo - peak outflow discharge
  • Qp10 - overbank flood control storage rate
  • Qp100 - extreme storm control storage rate
  • qp - water quality peak discharge
  • qu - unit peak discharge
  • r - volume of stormwater runoff
  • Rea - recharge area requiring treatment
  • Rev - recharge volume
  • RR - pollutant removal requirement
  • Rv - volumetric runoff coefficient expressing fraction of rainfall that is converted to runoff
  • S - soil specific recharge factor
  • tc - time of concentration
  • tt - time to drain filter bed
  • Vcp - channel protection volume
  • Vp10 - overbank flood control storage volume
  • Vp100 - extreme storm control storage volume
  • Vpp - permanent pool volume
  • Vr - rainfall runoff volume
  • Vre - recharge volume
  • Vs - snowmelt runoff volume
  • Vt - total volume
  • Vts - total storage volume
  • Vv - volume of voids
  • Vwq - water quality volume
  • Vwq ED - extended detention water quality volume
  • Zn - zinc

This page was last modified on 8 April 2013, at 14:11.

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