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would give them a little more of a head start, but they would still be small plants. Bioengineering would be used for the banks that will fit in with the existing structure. Brent Bogue explained that when this project is completed, it would look a lot like a natural stream with the vegetation and natural rocks and said that one new prefab bridge would go across. Commissioner Halkiotis said that he wanted to make sure that there would not be any cost to Orange County and staff agreed. He then asked about the third bridge. It was explained that one of the bridges, the Boy Scout Bridge, is being moved. Commissioner Halkiotis asked about the diameter of the pipe in reference to discharge. Staff explained that the pipes were 48 inches in diameter and Commissioner Halkiotis asked what happens when the discharge is shooting out "wide open" like in the case of Hurricane Fran. He wanted to know if this had been taken into consideration and what would happen to this restoration project. Brent Bogue said this was taken into consideration and that pools would be in place to dissipate the energy from the pipes. When seen in their natural flow state, the pools will look like little water falls. The pools would not be very deep but would be rock veins that come in from the side of the stream channel. When high flow comes out of the pipes the water would hit these stone veins, which would cause the water to turn a little bit and dissipate that energy rather than force it down the stream and erode the bank. It will be approximately a 10 to 15 foot wide diameter area and will look like a natural stream channel. Commissioner Gordan asked Paul Thames to speak about this from an engineer's viewpoint. Paul Thames said that putting things in a stream to change water velocity is a common way to prevent erosion. He said that putting the veins and dams in and spreading the flow out over a larger area will slow the water down. Restricting the flow of the same amount of water increases the velocity. And the energy in the veins causes the water to become turbulent in places as opposed to scouring. This is the kind of thing you want if you want to preserve a natural look. He said that you could make it mare efficient by getting the water out by just putting in a concrete flume. Commissioner Gordon asked if what Commissioner Halkiotis described, with the water charging through, would wash out the stream. Paul Thames said that all streams have some erosion when you have a storm of Katrina's magnitude. When Commissioner Halkiotis talked about how the water backs up, that is not the stream backing up, it is the Ena River. What happens in that case is that all the area will be under water just like it is now. That also dissipates the velocity. He said if you want a natural looking stream this is the way to create it. Commissioner Gordon asked if it would be possible to use some other kind of artificial or human made construction in the area near the Government Services Center where the stream is narrower. She said that the woods appear to be so close to the bridge that it doesn't seem safe for people walking back and forth. She asked if it was possible to do something else to slow the water down and do something that would prevent erosion of the Government Services Building, between the street and the first bridge, that wouldn't require people to go across the woods? Perry Sugg said there is not much that can be done. It is narrow and it is mostly rock structure. He said that what is usually done when a stream is this narrow is that planting is not done right up to the crossing and they leave a wider corridor. Commissioner Gordon asked if a retaining wall approach could be used since this is to be planted? That way, if you wanted to go from the Government Services Building to the Sheriff's Office you would not have to walk through the woods. She asked how far back the woods would be from the bridge.