On July 25, 2021 at approximately 10:17 a.m., it was reported that a manhole located at the intersection of Tangerine Farms Rd. and Clark Farms Blvd. was surcharging (which is called a Sanitary Sewer Overflow – “SSO”). Marana Water Department personnel responded immediately. Once onsite, it was noted that the water flowing from the manhole was naturally going into a stormwater retention basin immediately to the north of the subject location. It is estimated that 534,000 gallons of sewage diluted with stormwater came out of the manhole and was contained. This condition is believed to have been due to the extremely heavy rains experienced Saturday night through Sunday morning that inundated the sanitary sewer system.
The Arizona Department of Environmental Quality (ADEQ) was notified immediately, and crews ensured that appropriate traffic measures were in place along with applying traffic pylons and warning signs around the perimeter of the retention basin stating that an SSO had occurred and to stay away from the area. In addition, the intersection where the manhole is located was cleaned and disinfected late Sunday afternoon.
On July 26, 2021, an ADEQ inspector met with Marana Water staff to perform an investigation and to provide further guidance. Marana Water staff has taken additional measures, which included installing temporary fencing around the perimeter with warning signs, and on Wednesday morning will be gradually pumping down the retention basin and transferring the diluted sewage back into the sanitary sewer system. Once completed, the area in and around the retention basin will be cleaned up as needed.
