CEDAR FALLS - Lightning is believed to have struck the wastewater treatment system in Cedar Falls knocking out both the alarm system and some pumps at the treatment plant.

As a result, an estimated 750,000 gallons of untreated sewage was bypassed to the Cedar River between 2 a.m. and 7 a.m. when the problem was discovered and fixed.

The Iowa Department of Natural Resources is advising that precautions be taken for at least the next 24 hours for people using the Cedar River below Cedar Falls due to the likelihood of elevated bacteria levels.

Those precautions include:

Avoid swallowing the water

Avoid the water if you have open cuts or wounds that could become infected by contact with bacteria

Swimming is not recommended for persons who are very young or very old and may have problems avoiding ingestion of water, and people who have weakened immune systems due to other medical conditions.

Meanwhile, a number of wastewater facilities around the state were reporting overflows because of excessive rain during the night.

While a mechanical failure led to the Cedar Falls discharge, other communities across the state are likely discharging wastewater after heavy rains overwhelmed collection and treatment systems Late Sunday evening and early Monday morning.