| Review Type |
Outcome |
Est. Completion Date |
Completed |
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Engineer Review - Grading
|
Approved with Conditions
|
09/13/2024
|
08/29/2024
|
|
|
Gene Williams, P.E.
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Miscellaneous Correction
Corrective Action Required
The original proposal was to place a flat-grated top over the outlet structure. The last applicant letter requested an analysis of providing a raised or domed grated top. The question should have been "do you really need a grated top for this outlet structure?". Is a grated-top required for this application? There are instances within the City (e.g., Lakewood Lake, tributary #1 reservoir) where a grated-top is not installed and does not seem to be a maintenance issue. Please review and evaluate whether a grated-top is required.
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Miscellaneous Correction
Corrective Action Required
The grated-top shown on the plans does not contain the level of design detail necessary to evaluate the design. For instance, there is no pictorial representation of the bracing that will be utilized to keep the large grate from sagging under its own weight. There is a note on the typical section view toward the top of the detention basin plan sheet specifying some kind of support mechanism, but without a drawing, this is difficult to decipher both for inspections personnel with the City and the contractor. In addition, there are no dimensions showing the height of the grated-top in relation to the bottom of the grate (i.e., how tall is the grated top?). Finally, there is no way to access the large outlet structure in the future given the design you are proposing. An access is required, and should line up with the stairs in the outlet structure that appear to be located on the north side of the outlet structure. If you desire to place a grated-top over this very large outlet structure, it would appear a high-hat style grated opening would be more appropriate. This would include a reinforced concrete top with access for maintenance in the form of a access panel, and grated-sides that are more or less vertical and open for flow. Please evaluate and review, and provide a more robust design for this grated-outlet structure. Finally, see comment #1. There may not be a need to provide any grated inlet for this particular application. You will need to perform your own risk assessment concerning a lack of preventative measures for keeping people, pets, etc. from accidental entry into the outlet structure.
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Miscellaneous Correction
Corrective Action Required
Informational Comment: The MDNR Dam Safety Program informed me they will be performing a post-construction survey of the dam to ensure it does not fall under their jurisiction in terms of dam height. Please ensure your plan will meet the requirements of the MDNR Dam Safety Program, as the City does not have any jurisdiction over MDNR's Dam Safety Program rules or regulations.
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Miscellaneous Correction
Corrective Action Required
Informational Comment: Contingent upon the dam construction not falling under MDNR Dam Safety Program rules, no additional cost estimate or payment of additional Engineering Plan Review and Inspection Fees will be required for this particular project. If it is later determined that the MDNR Dam Safety Program has jurisdiction over the dam and requires it to be removed and re-constructed, re-designed, etc., additional fees would be required for the difference in scope.
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Engineer Review - Grading
|
Corrections
|
08/02/2024
|
08/01/2024
|
|
|
Gene Williams, P.E.
|
|
|
Miscellaneous Correction
Corrective Action Required
The original proposal was to place a flat-grated top over the outlet structure. The last applicant letter requested an analysis of providing a raised or domed grated top. The question should have been "do you really need a grated top for this outlet structure?". Is a grated-top required for this application? There are instances within the City (e.g., Lakewood Lake, tributary #1 reservoir) where a grated-top is not installed and does not seem to be a maintenance issue. Please review and evaluate whether a grated-top is required.
|
|
|
Miscellaneous Correction
Corrective Action Required
The grated-top shown on the plans does not contain the level of design detail necessary to evaluate the design. For instance, there is no pictorial representation of the bracing that will be utilized to keep the large grate from sagging under its own weight. There is a note on the typical section view toward the top of the detention basin plan sheet specifying some kind of support mechanism, but without a drawing, this is difficult to decipher both for inspections personnel with the City and the contractor. In addition, there are no dimensions showing the height of the grated-top in relation to the bottom of the grate (i.e., how tall is the grated top?). Finally, there is no way to access the large outlet structure in the future given the design you are proposing. An access is required, and should line up with the stairs in the outlet structure that appear to be located on the north side of the outlet structure. If you desire to place a grated-top over this very large outlet structure, it would appear a high-hat style grated opening would be more appropriate. This would include a reinforced concrete top with access for maintenance in the form of a access panel, and grated-sides that are more or less vertical and open for flow. Please evaluate and review, and provide a more robust design for this grated-outlet structure. Finally, see comment #1. There may not be a need to provide any grated inlet for this particular application. You will need to perform your own risk assessment concerning a lack of preventative measures for keeping people, pets, etc. from accidental entry into the outlet structure.
|
|
|
Miscellaneous Correction
Corrective Action Required
Informational Comment: The MDNR Dam Safety Program informed me they will be performing a post-construction survey of the dam to ensure it does not fall under their jurisiction in terms of dam height. Please ensure your plan will meet the requirements of the MDNR Dam Safety Program, as the City does not have any jurisdiction over MDNR's Dam Safety Program rules or regulations.
|
|
|
Miscellaneous Correction
Corrective Action Required
Informational Comment: Contingent upon the dam construction not falling under MDNR Dam Safety Program rules, no additional cost estimate or payment of additional Engineering Plan Review and Inspection Fees will be required for this particular project. If it is later determined that the MDNR Dam Safety Program has jurisdiction over the dam and requires it to be removed and re-constructed, re-designed, etc., additional fees would be required for the difference in scope.
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Engineer Review - Grading
|
Corrections
|
07/05/2024
|
07/05/2024
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|
|
Gene Williams, P.E.
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|
Misc
Corrective Action Required
Please show a plan view of the grating on top of the outlet structure. It is difficult to determine what is being proposed without a plan view.
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Corrective Action Required
Would it be better to show a "raised" grating for the top of the outlet structure, or "domed" grating?
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Miscellaneous Correction
Corrective Action Required
The stormwater study dated June 2024 should be re-named to "Final Stormwater Study" or equivalent rather than "Preliminary".
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