Effective stormwater conveyance on urbanized watersheds is currently an important issue in Poland due to laws and economic aspects associated with protection of aquatic environment. It is additionally motivated by long-term negligence in the stormwater management in Polish cities of any size. Storage tanks are the basic devices to effectively control the flow rate in drainage systems during wet weather. Presented here is the conception of vacuum-driven detention tanks allows to increase of the storage capacity by usage of space above the free surface water elevation at the inlet channel. Partial vacuum storage makes it possible to gain cost savings by reduction of both the horizontal area of the detention tank and necessary depth of its foundations. The ability to quick emptying of stormwater stored under the vacuum conditions is the additional advantage of such reservoirs in urban drainage systems. The paper also describes in detail each of the main operational phases (control rules, boundary conditions and basic equations) and some economic issues associated with vacuum usage in storage reservoirs.
- storage tanks
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