Mark Yates and Kevin Smith from the Elgin Public Works begins investigating if there were chemicals dumped into Tyler Creek near Davis Road and Rt. 31 in Elgin, Ill., on Tuesday, April 3, 2012. | Kevin D. Sherman ~ For Sun-Times Media
Mark Yates and Kevin Smith from the Elgin Public Works begins investigating if there were chemicals dumped into Tyler Creek near Davis Road and Rt. 31 in Elgin, Ill., on Tuesday, April 3, 2012. | Kevin D. Sherman ~ For Sun-Times Media
Mark Yates and Kevin Smith from the Elgin Public Works begins investigating if there were chemicals dumped into Tyler Creek near Davis Road and Rt. 31 in Elgin, Ill., on Tuesday, April 3, 2012. | Kevin D. Sherman ~ For Sun-Times Media
A crew from the Elgin Public Works begins investigating if there were chemicals dumped into Tyler Creek near Davis Road and Rt. 31 in Elgin, Ill., on Tuesday, April 3, 2012. | Kevin D. Sherman ~ For Sun-Times Media
Mark Yates from the Elgin Public Works begins investigating if there were chemicals dumped into Tyler Creek near Davis Road and Rt. 31 in Elgin, Ill., on Tuesday, April 3, 2012. | Kevin D. Sherman ~ For Sun-Times Media
Waters run yellowish-green in Tyler Creek Forest Preserve on Monday near Route 31 and Davis Road in Elgin. The unknown substance flowing in Tyler Creek is under investigation. | Janelle Walker~For Sun-Times Media
Kevin Smith from the Elgin Public Works begins investigating if there were chemicals dumped into Tyler Creek near Davis Road and Rt. 31 in Elgin, Ill., on Tuesday, April 3, 2012. | Kevin D. Sherman ~ For Sun-Times Media
Elgin public works employees Mark Yates and Kevin Smith check Tyler Creek under Route 31 on April 3 to find the source of a substance found in the creek. | File~Sun-Times Media
ELGIN — A crew from Elgin’s Public Works Department hoped that by running a TV camera through a few thousand feet of storm water pipe Tuesday, they could discover where a yellow substance flowing into Tyler Creek over the past few days might have originated. …