An emergency cleanup of the water pollution in the Ayalon and Yarkon streams in Tel Aviv will be started Friday. A pipe bringing sewage from the Ono Valley communities to the Shafdan Sewage Treatment Center burst on February 9, causing an intermittent sewage flow through the streams and into the Mediterranean Sea over the past month and a half. The makeshift Shtulim Dam on the Ayalon Stream had generally stopped the flow but it has burst several times because of heavy rains and other factors. Earlier this week, the dam broke again, sending sewage cascading down the waterway. Many of the Yarkon's fish were killed and had to be removed. "The Authority has contracted a company to begin pumping water from the Shtulim Dam on the Ayalon stream back into Egodan - Environmental Infrastructure's pipes, bypassing the damaged section, starting tomorrow. While they cannot pump all of the water out, they can handle most of it," said Danny Greenwald of the Water Contamination Control at the Water Authority. The flow of sewage from the burst pipe, which has forced the closure of Tel Aviv's beaches several times and threatens the swimming season set to open just before Pessah, had been stopped at the makeshift Shtulim Dam. However, the dam has broken several times more in the heavy rains over the last month and a half, allowing a rampant flow of sewage. The Health Ministry will monitor the situation and release a statement to the public as soon as the water is safe to swim in. "In addition, the Ayalon sewage treatment plant run by Mekorot will divert the treated water that was flowing into the Ayalon Stream to the Sorek Stream, thereby lessening the chance that the dam will break and allow sewage to flow into the Yarkon and the Mediterranean Sea. The dam should prevent any remaining sewage reaching the stream or the sea," Greenwald said. The company contracted for the pumping is also building a 120-meter bypass of the problematic section to a new alternate piping infrastructure. The bypass is currently being built in hopes that it will create a more permanent solution to the problem.They hope to have it completed within 10 days. The alternate set of pipes has been under construction for the past two years and recently reached the area of the break, making a bypass feasible now. The dam cannot be made permanent because it would increase the risk of flooding in the Tel Aviv neighborhoods of Ezra and Hatikva during heavy rains. As it is, the neighborhoods are low-lying and vulnerable to flood damage, Yarkon Stream Authority Head David Pargament said. While the Water Authority is acting according to the Water Law to rectify the problem on an immediate and permanent basis, there is a debate about where the ultimate responsibility for the burst section lies and who will pay the Water Authority back. The Environmental Protection Ministry has invited the mayors of Or Yehuda and Kiryat Ono to hearings next Wednesday to discuss their responsibility for the incident. Or Yehuda spokeswoman Nurit Netanov said the city was not responsible for the section of pipe that had burst, because it was beyond the municipal boundaries. "We are certainly not responsible for fixing it. We are merely the last stop before the Hiriya [garbage dump], but there is sewage flowing along the line from all the Ono Valley communities, and not just us. We have checked and cleaned the line within our jurisdiction and haven't found any problems," she said. Netanov laid the blame on the Hiriya for dumping tons of construction and demolition waste on top of sections of the pipe, blocking access to it. On Sunday, World Water Day, the Knesset Social-Environmental Lobby headed by MKs Dov Henin (Hadash) and Ophir Paz-Pines (Labor) plan to tour the Yarkon with government officials.