As of approximately 11:30 A.M. on August 18, 2023, The Town of Billerica WRRF has been partially bypassing its tertiary treatment process as well as entered contact stabilization mode in aeration due to exceptionally high flow conditions. Contact stabilization is an alternative flow pattern utilized in extreme conditions to preserve the microlife in the plant that is essential for Wastewater Treatment. All flow is still going through Pretreatment, Primary Treatment, Secondary treatment, receiving partial biological treatment, partial tertiary treatment and 100% of flow is going through Disinfection as always. These alternative flow modes/bypasses are being utilized at this time to provide the highest quality effluent possible while preserving operational capabilities of the plant during this high flow event. This high flow is a result of heavy rainfall received on the morning of 8/18/23 which has substantially raised the level of groundwater and caused widespread flooding in the area. These levels can take several days to subside. Again, The Town of Billerica WRRF (NPDES # MA0101711) is currently still receiving and treating unprecedented high flows in excess of 12 Million Gallons Per Day to be discharged to the Concord River.
Under 314 CMR 16.04 (1)(b-e), The Town of Billerica WRRF is required to include the following language:
" Precautionary measures to be taken by the public. Avoid contact with these water bodies for 48 hours after the discharge or overflow ceases due to increased health risks from bacteria and other pollutants."
"The discharge or overflow consists, or likely consists of untreated or partially treated sewage and waste."