score = (x) -> 
  if x == "Yes"
    10
  else
    0
  
weights = [0.25, 0.25, 0.25, 0.25]
water_quality = [pressure_reduction, discharge_water_quality, reporting, pressure_reduction_targets]

weights.reduce((weighted_sum, weight, index) -> 
              weighted_sum + weight*score(water_quality[index])
             , 0)