A circular settling tank is to be designed for primary treatment of sewage at a flow rate of $10$ million liters/day. Assume a detention period of $2.0$ hours and surface loading rate of $40000$ liters $/ \mathrm{m}^{2} /$ day. The height (in meters) of the water column in the tank is $\_\_\_\_\_\_\_$ (rounded off to $2$ decimal places).