Professor Lea Wittenberg, an expert on forest fires and soil erosion from Haifa University, says, "In Haifa, due to impermeable surfaces—unlike open spaces—heavy rainfall isn't absorbed and becomes a flowing, urban river. After the recent fires, there is still a large amount of ash and other contaminants on the surface which can be swept into drainage and cause flooding, which can damage the drainage system and nature."
According to Wittenberg, most areas in Haifa are covered with a layer that prevents rainwater from being absorbed into the ground, which causes surface runoff. Runoff can become flood water in normal conditions, but the added issue of surface contaminants from the fires makes matters worse.
"This situation could lead to flooding and damage to areas burned and those adjacent to them as a result of the pollution load. This could increase runoff and urban erosion where the concern is damage to infrastructure, ecosystems, and contaminating the sea, where the water ultimately flows," warned Wittenberg.
David Luria, head of the Rehabilitation Administration, which was established in Haifa in order to deal with the damage caused by the fires, said that the city is prepared to deal with the winter weather, especially the difficult conditions caused by the fires. "As part of the preparations against erosion and contaminants which could make their way into the drainage systems, all drains were cleaned and treated by staff to ensure as much free flow as possible."
Luria added that in the Romema neighborhood, which was heavily affected by the fires, pumps and other sewage treatment equipment have already been brought in. Additionally, special tarps are being handed out by the city in an effort to prevent further rain damage to structures affected by the fires.