Laserfiche WebLink
Susan Burgmaier -3- June 17, 2014 <br />C -G3, the Division cannot approve removal of Culvert C -F4. If the receiving structures <br />would need to be enlarged to cant' the design event, they would need to be reconstructed <br />at the time of removal of Culvert C -F4. Please either provide revised designs for <br />Ditch D -D3 and Culvert C -G3 to include the increased flow resulting from the <br />removal of Culvert C-F4, or revise the revision application materials to retain <br />Culvert C -F4. <br />BRL: Culvert F4 will be removed. Please see revised designs for Ditch D -3 and culvert G- <br />3. Ditch D -3 was re -built in 2012 under MR -131. The channel gradient varies from 20- <br />50%. In -place riprap varies in size from 12"-21". The design provided is for ditch <br />segments of 20% and of 50 %. <br />6. DRMS: The cover letter for the revision application indicates that Culvert C -G2 will be <br />removed, and it appears to have been removed from the review copy of Map 15 -3. It is <br />not clear on the review copy of Map 15 -3, however, how flow from Ditch D -D4 will be <br />conveyed to Pond D. The application materials include a design (Structure Detail) for <br />Culvert C -G2 with an indication that a 12" pipe will be installed, and the cost estimate <br />indicates that the culvert will be resized but retained. Please clarify whether Culvert C- <br />G2 will be removed or relocated and /or resized, and if it is to be relocated/retained, <br />please indicate its location on the review copy of Map 15 -3. If the culvert is to be <br />removed, please provide a clear indication, on Map 15 -3, of where Ditch D -D4 will <br />enter Pond D. <br />BRL: The cover letter should have stated Culvert G2 will be relocated. The review copy of <br />Map 15 -3 does not show in the where Culvert G2 will be relocated, but the schematic <br />prepared showing the plan and profile of Pond D does. Culvert G2 will be located under <br />the access road into the revised material storage area. Please see the attached review <br />map showing the location of Culvert G2. <br />7. DRMS: The Structure Detail for Culvert C -G2 indicates that the design flow is 0.42 cfs. <br />The Subwatershed Hydrology Detail table shows a design flow of 11.77 cfs. If Culvert G- <br />G2 is to be retained, the Structure Detail must be revised to be consistent with the <br />Subwatershed Hydrology Detail output. <br />BRL- The SWS Hydrology detail does show Culvert G2 with a peak flow of 0.42 cfs. The <br />Peak flow of 11.77 cfs is for Structure #1 (Pond D). <br />8. DRMS: The Division has reviewed the reclamation cost estimate provided by BRL, and <br />has the following comments: <br />a. BRL did not include increased costs for the reclamation of the enlarged Pond D. <br />Please provide a revised backrill volume estimate, the proposed storage <br />location (during the operational phase) for material excavated to expand the <br />pond, and a revised cost estimate for reclamation of the enlarged pond. <br />b. BRL is requesting credits for removal of the unnamed culvert into Pond D and for <br />