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<br />- 3,
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<br />run did create somewhat accurate results for the June 17'h, 1965 storm event, with a large rainfall center near Falcon,
<br />Colorado, as was originally reported, Mr, Henz mentioned that the NCAR inflow winds were around 15 knots, whereas the
<br />observed winds on those days were much greater. Dr. Tomlinson said that Mr, Dansereau was addressing these issues, and
<br />has taken these new computer model runs to task and hopes to recreate the original storm patterns as accurately as possible,
<br />Mr, Nolan Doesken asked if it is such a good idea to change the MM5 model to such a low resolution, Dr, Tomlinson replie
<br />that the model is stable at this time in the storm run, and that Mr, Dansereau and A W A have gone to a level that is beyond
<br />what was originally planned in order to produce accurate results from the model. Dr. Tomlinson jokingly mentioned that M
<br />Dansereau has sort of taken this task "personally,"
<br />
<br />On the subject of the project budget, Dr, Tomlinson mentioned that there was nothing out of the ordinary to report, except fo
<br />an unpaid invoice by Douglas County, Ms, Fox stated that this would be taken care of and provided an address for which to
<br />send a new invoice, He also mentioned that the Colorado Water Conservation Board (CWCB) has not been billed since the
<br />end of last year, but will be invoiced by A W A once Interim Report #2 is sent out to the TRC,
<br />
<br />At this time, Mr, Lang stopped the presentation to introduce Mr, Mike White of the USACE Northwest office, Mr, White
<br />stated that the reason he had attended this meeting was because he was interested in the progress being made, as well as bein
<br />interested in the future reports that will be distributed, He added that he is anxious to see what the future holds for this
<br />project. Mr, Lang welcomed him to the meeting and welcomed all suggestions by the USACE. He went on to say that
<br />Interim Report #1 has been completed and this meeting will discuss some of the preliminary PMP values, Mr, Lang stated
<br />that the CWCB has had constant communications with the USACE and have talked to the project sponsors about the ensuin!
<br />PMF project that will follow the PMP study, He said that the PMF would be run using the USACE model.
<br />
<br />Mr, White asked how different the A W A PMP values were as compared to the original NWS PMP values, Dr. Tomlinson
<br />said that the comparisons were not going to be made yet, but the largest A W A value results currently in a PMF event that
<br />places the Cherry Creek Reservoir elevation ten feet below the crest of the dam, He mentioned that Mr, Trieste would
<br />discuss this in more detail later in the meeting,
<br />
<br />Presentation #2 bv Dr. Ed Tomlinson
<br />Dr, Tomlinson began a presentation that showed the differences between the A W A and NWS methods of calculating PMP
<br />values for the Cherry Creek Drainage Basin, The following are excerpts from his slides, which he provided in paper copies
<br />to t)).j: meeting attendees:
<br />
<br />. The NWS HMR PMP development procedure provides rainfall values that are theoretically the greatest rainfall amounts
<br />that Can fall over the basin, At this time, there are no technologies to develop theoretical rainfall values from the origin,
<br />principles, Historical rainfall observations are used, and the largest storms are identified over regions that are
<br />topographically and climatologically similar to the study area, A standard procedure is applied to the storm depth'area-
<br />duration analysis to produce the greatest theoretical rainfall values over the drainage basin in question,
<br />
<br />. This NWS HMR approach provides generalized PMP analyses, As mentioned above, the largest storms are identified
<br />throughout the study region and the standard procedures are applied to produce the greatest theoretical rainfall for each (
<br />the areas within the region that are topographically and climatologically similar to the study area, These rainfall values
<br />are enveloped and smoothed on a curve to produce PMP values that are provide continuity over the region, Enveloping
<br />is the method in which the largest storm values are used to adjust and analyze the remainer of the major storms in the
<br />study region,
<br />
<br />. With the first Cherry Creek PMP study, the NWS started with the generalized PMP regional values from the HMRs,
<br />which where enveloped and smoothed analyses developed from the largest storms identified in the topographically ,
<br />and climatologically similar region of the HMR, This widespread generalized analysis was then applied to the very
<br />specific region of the Cherry Creek Drainage Basin,
<br />
<br />. In comparison, A W A begins the site, specific PMP study by gathering and analyzing observed localized rainfall
<br />values, The same procedures as used by the NWS for the HMRs are applied to the A W A study, but to a very specifi
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<br />Flood Protection. Water Project Planning and Financing. Stream and Lake Protection
<br />Water Supply Protection. Conservation Planning
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