Bright green rivers in Wauwatosa are an unusual sight.
But there is no need for concern as the city is using the harmless dye to indicate where the sanitary sewer system is in need of repair.
Beginning Monday, July 10 workers from the company Visu-Sewer began pouring the non-toxic dye into storm sewers to look for any areas where dyed water is entering the sanitary system, indicating a repair is needed.
Work typically occurs between 7 a.m. and 5 p.m. on weekdays. Testing will be completed by late September.
Visu-Sewer has an office in Pewaukee and, according to its website, describes itself as a "provider of all of the services necessary to keep underground infrastructure operating at optimum flow and performance."
After the placement of the dye, the contractor videos the sewers looking for damage. When this process is completed the dyed water will drain from the storm sewer pipes into Underwood Creek and the Menomonee River.
The city said that the Milwaukee Metropolitan Sewerage District and the Wisconsin Department of Natural Resources are aware of the work and agree it is safe for the creek, river and associated wildlife.