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Mr. Wilson said it is possible but it does not meet the objective of trying to stabilize the channel, and it creates a condition where the water will back up at that point. Staff can design around the culvert, but it does not meet the design goals of this project. Ms. Hosterman noted that heavy debris blocks the creek and does not allow any water to get through after a heavy storm. She asked if it would be possible to reintroduce some type of stream crossing that would be more substantial than stepping stones in a low flow situation. Mr. Wilson said it is possible to construct a bridge. The estimated cost is approximately $60,000 per bridge. Staff is proposing to leave the upper most crossing in place, which is an existing culvert, as it is not part of the major section of the flow, and as an option, remove the culvert and replace it with a bridge. He indicated that this crossing is a major point of access from Kottinger Creek to the Park. Staff believes this needs to be separated from the water and either be the culvert crossing or a bridge. In staff's opinion, this crossing would be a higher priority as opposed to the middle crossing. For the final design plans, Mayor Pico asked if it was possible to look at a potential option for a bridge to be placed in the middle portion of the Creek across from Sharab Court. Mr. Wilson said yes. Ms. Hosterman noted lhat over the past several months, residents who live downstream have had major concerns about the potential for future flooding. She believed this was true not only with the detention ponds but also with the actual change in the design of the creek. She believed that by cleaning the creek, it would be restored to its natural, meandering state and it would probably slow future flow and benefit the downstream neighbors pertaining to flooding issues. Mr. Wilson indicated that at the beginning of the project, staff believed that the change in design of the creek and cleaning it out would slow water flow down and provide some benefit. The design creates a straight flow going through, which does not help nor hinder the flows downstream, and it basically relieves the water flow in almost identical velocities. The velocities actually go up a bit, but because it is a smoother type of flow going through, there is less erosion in the water. The water flow basically does not change and the nature of the water is somewhat better. Staff needs to be vigilant about maintaining the detention basins. Staff goes out to the creek every year and tries to pick up as much vegetation as possible before the storms begin. The major issue for flooding in the City is not the .capacity of the system, but debris getting in the way and blocking the detention basins, which cause flooding. The installation of the detention basins upstream has created a significant improvement in terms of the amount of water flowing downstream. It also reduces the flow by 86 percent, which is significantly less than what it was in 1986. Pleasanton City Council 9 07/20/04 Minutes