FLOOD03506 - Laserfiche WebLink

Home Browse Search

I I I I I I I I I I I I I I I I I I I Mr. Ben Urbonas, P.E. Page Three September 26, 1977 Mr. Ben Urbonas, P.E. Page Four September 26, 1977 2. Reach II-B (Garrison Street to Rockmont Ponds). The District, on Sanderson Gulch, has set a precedent by working with private owners of downstream ponds; i.e., Green Gables Country Club, to make specific improvements in those ponds which benefit other taxpayers and also those agreements contained pro- visions for the preservation of such improvements after they have been completed. Also, an agreement was entered into on Lena Gulch with Consolidated Mutual Water Company regarding private improvements. Englewood and Holly Dams have also involved the private sector in agreements concerning them and the surrounding improvements. Therefore, if from an engineering standpoint the benefit/cost analysis referred to on Page VIII-4 of the report is substantiated, it would not be difficult to work out a satis- factory arrangement among Rockmont College, the City of Lakewood and the District to enlarge the ponds and maintain them. which will increase flows but which will not have an adequate outlet to leave the area. Just because development has taken place over a natural drainage channel, this does not entitle a governmental entity to solve the problem upstream by sending more water at a faster rate on the development which is en- croaching in the channel. It is my opinion that the modifications to the embankment and/or spillway of the Rockmont Ponds required by the State Engineer be carried out at the sole expense of the owner whether the ponds are to be enlarged or not. Further, based on the pre- vious policy of the District, the enlargement of the Rockmont Ponds should not be ruled out as an alternative and after further engineering analysis, if the alternative of pond enlargement is selected,attempts should be made to reach an agreement with Rockmont College before looking to another alternative. See Page Seven of letter from W. Jospeh Shoemaker to Wright-McLaughlin Engineers, re: Lena Gulch Master Plan With Proposed Alternatives, dated January 28, 1974, a copy of which is attached hereto and incorporated herein. This problem is similar to the problem with the Red Barn Blockage of the Natural Watercourse referred to in that letter, except that we have here the added problem of the inadequate size of pipe under Wadsworth Boulevard and under the Auto Complex. It is my opinion that the suggested alternative in the report is not legally safe because of the proposed improvements upstream and what appears to be the increased flows in quantity and speed at Wadsworth Boulevard. Therefore, it is my suggestion that the engineers detail all additional flows from the IOO-year event which will occur as a direct result of upstream improvements from Wadsworth Boulevard which are suggested in the report. The engineers must then make a recommendation on what is to be done with those additional flows, since if they are not dealt with properly, the City of Lakewood and the District will incur lia- bility for those additional flows which would not have occurred but for the suggested improvements. Further review of this Reach will probably be necessary after the engineers revise their alternatives. 3. Reach III (Rockmont Ponds to First Avenue). In the alternative suggested, no flood plain delineation is recommended. It is my opinion that this is necessary with the structural improvements that are also being recommended in this reach. Also, a flood plain delineation is necessary due to the diverse flooding which is presently indicated in the area by the Drainage Basin Boundary map and the necessity of notifying residents of the flood plain. 5. Reach V-B (Auto Complex to Reed Street). It is recommended that a grass-lined channel be constructed just West of Reed Street, and that as a part of such construction a single- family residence be removed in order to build the channel. Further, it is suggested that the residence be purchased when it comes on the market in order to minimize the sociological impact of this alternative. It should be noted that, if the quantity or velocity of the flows reaching this residence will be increased by the suggested improvements upstream of the residence, the residence must be purchased before the improvements upstream are made, or the District and the City of Lakewood will be subjected to liability for damages caused by these increased flows. These 4. Reach V-A. (Wadsworth Boulevard to Auto Complex). With respect to the proposed improvements in Reach III and IV, and the description of the Basin on the East side of Wadsworth, as des- cribed on Page VIII-5 of the report, the impression is left that the engineer's recommendations will ultimately send surface waters onto the property owners adjacent to Wadsworth Boulevard in more quantity and at a faster rate than previously. I would believe this change in conditions would subject the City of Lakewood and the District to liability, since an improvement will take place ~2