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Josie Thomas, 230 Wyndham Circle, asked about the elevations of the other sites and how the integrity of the existing containment is checked. On what kind of schedule is the checking done? Thomas said she was concerned the clearing of the trees would change the drainage on the site. Wexford Heights lies below the reservoir. Kramer said the other available site for the new reservoir is in Edina, which is the second choice. The Edina site is less desirable because it is low and would require a $1 million pumping station. When Minneapolis has reservoirs at both the New Brighton and Edina sites, Minneapolis would have two days’ water storage. The priority is to get the New Brighton site built. Then, Minneapolis would like to build a reservoir on their site in Columbia Heights. The Fridley site is almost totally developed. Thomas asked again about the checking the reservoir for water containment. Kramer said that they designed the reinforced concrete reservoir for 100-year storage. The City of Minneapolis repaired the Columbia Heights reservoir few years ago. Minneapolis built that reservoir in the 1800's. The reservoirs are checked every ten to fifteen years. The concrete installed at the Columbia Heights reservoir in 1913 now tests out at 7,000–8,000 pounds per square inch, which is an excellent number. Modern concrete will not fail. Izraelev explained the structural design of the proposed reservoir. Kramer said the City of Minneapolis would hire a consultant to go over the design. Kramer said the concrete in reservoirs, because it is moist, cures well and becomes stronger. The reason Minneapolis inspects the reservoirs only every 10 to 15 years is that a reservoir must be drained and a thorough inspection done from the inside. A pictorial record is kept. The reservoir is cleaned and chlorinated. The reason there was damage at the Columbia Heights reservoir, built in 1897, is trees were growing on top of the reservoir. Also, it was built using old-style concrete. Now, the Minneapolis Water Works keeps roots away from the structures. Thomas asked about the change of drainage on the site and where would it be directed. Whitaker said the roof of the reservoir, which is under the soil and on top of the concrete, will have a roofing membrane that will collect water. There will be a drain tile system around the perimeter of the reservoir. The drainage from the roof will not impact Wexford Heights. The drainage from the rest of the site will not change. The water will be directed to a storm sewer or a low area on the property. Whitaker stated Minneapolis would complete the drainage design later. The rehab of the Columbia Heights site included installing a roof membrane and drain tile. Mattila stated the Rice Creek Watershed District and the City Engineer must approve the drainage plan. Bill Thomas, 230 Wyndham Circle, stated the reservoir would be 30 feet from the edge of the road and Minneapolis is proposing small Caragana and Amur maples. All the large trees will be cleared. Thomas stated the Minneapolis people have done a really good job of not telling how thick the walls of the tank are going to be. Izraelev responded the walls would be 24 inches thick. Kramer pointed out they would plant trees on the boulevard. Craig Faher, 420 Wyndham Circle West, said he was concerned about the loss of thousands of trees from this beautiful undeveloped area. The property has wildlife habitats and a significant deer herd. The length of construction is pretty frightening for adjacent property owners. Two and a one half years are a long time to deal with noise and dirt. Whitaker said we could address the time line in the contract. Whitaker stated he felt two and a half years was too long a construction estimate. Kramer commented that two and a half years would include site clearing, fill compaction, and the actual construction. There would be periods where there would be no activity on the site. I:\COMMISSIONS\PLANNING\MINUTES\1996\09-17-96.WPD 3