December 15, 2006 Mr. Marc Melinkoff Christopher A. Joseph & Associates Environmental Planning and Research 30851 Agoura Road, Suite 210 Agoura Hills, CA USA 91301 Re: Wind Impact Assessment Marina del Rey Tower Marina del Rey, California RWDI Reference No. 07-1161 Dear Mr. Melinkoff: Email: marc.melinkoff@cajaeir.com As per your request, this letter summarizes our professional opinion on the effect of the proposed Marina del Rey Tower on wind conditions within the adjacent Basins, the potential loss of surface winds used by birds and the general air circulation in Marina del Rey. This wind impact assessment includes a review of the project drawings, aerial photographs, regional wind data, the results of previous wind studies conducted by RWDI on projects in Marina del Rey, and our knowledge and experience. A qualitative study in lieu of a full wind tunnel model study is appropriate for the current development, considering the location and size of the development, the local wind directionality and the availability of test data from other projects in the area. Description of Proposed Development Schematic drawings and renderings for the proposed project were provided by Christopher A. Joseph & Associates on November 24 and 29, 2006 and can be found in Appendix A. The proposed development is a residential tower of 25 storeys (approximately 366 ft high) with a seven-storey podium (approximately 80 ft high). This tower is located between Lincoln Boulevard and Admiralty Way, approximately 450 ft northeast of Basin F.
Local Wind Directionality Figure 1 shows the directional distribution of seasonal winds, based on long-term wind records from the nearby Los Angeles International Airport. These wind roses show the percentage of the time that wind blows from each of the 16 compass directions during the spring, summer, fall and winter seasons between 7:00 am and 9:00 pm, when most sailing would occur. It is evident that winds from the west, west-southwest, southwest and east directions are most dominant throughout the year. Wind-tunnel Studies for Other Local Developments Of the many wind studies conducted by RWDI on projects in Marina del Rey since the 1990's, both the Fisherman s Village and the13900 Fiji Way project are on the east side of the Main Channel, similar to the current development. In our September 17, 2004 report 1 for the Fisherman s Village, it was concluded that Athe proposed Fisherman s Village will not affect the existing wind conditions over a majority of the areas of Marina del Rey. There will be areas of altered wind speeds and directions in the Main Channel adjacent to the proposed development when winds are from the east. This is not an issue considering the boating activities in these localized areas. Due to the localized nature of these changes and the low frequency associated with the easterly winds, there will be no significant effect on the general air circulation patterns within the Main Channel and Basins in Marina del Rey. The Fisherman s Village development was four storeys in height. The wind tunnel study illustrated that easterly winds flowing around the development had basically resumed their existing direction and speed approximately 300 ft downwind of the development, and that 500 ft away there was no perceivable difference between the existing and proposed configurations. The 13900 Fiji Way project consisted of four towers, ranging in height from 80 ft to 140 ft. Again, the wind tunnel study illustrated that easterly winds flowing around the development had generally resumed their existing direction/speed approximately 400 ft downwind from the site, and by 1000 ft downwind there was no impact. Effect on Sailing Conditions When winds flow around a building, accelerations occur around the windward building corners and decelerations in the wake area on the leeward side of the building. High turbulence in the wake area is usually associated with variations in both wind direction and speed. 1. RWDI Project Number 04-1692, Wind Study, Fisherman s Village, Marina del Rey, California.
December 15, 2006 Mr. Melinkoff Christopher A. Joseph & Associates Page 3 The proposed Marina del Rey Tower is located 450 ft to the northeast of Basin F, which is on the east side of the Main Channel, and runs in a southwest and northeast direction. When winds are from the most frequent west-southwest and west directions, the acceleration and deceleration zones around the proposed facility will mainly be on land, not on the water surface. The westerly and southwesterly winds will accelerate around the southeast corner of the proposed development and alter the wind speed and direction in the area immediate east of the development. As the west winds are frequent, accelerations at the base of the tower could occur on a regular basis. It is a positive design feature to not include any entrances in the vicinity of the southeast corner of the development, as this area is expected to have localized accelerations due to the alignment of the tower with the prevailing winds. When winds are from the east direction, the wind effect will extend onto Admiralty Park, west of the proposed facility. These effects are not expected to extend into Basin F. With the proposed development in place, wind conditions would not change in other Basins or in the Main Channel of Marina del Ray for any wind directions. Loss of Surface Winds Utilized by Birds In order to assess the effect of changes to surface winds on birds, a report (see Appendix B) was prepared by an expert in aerodynamics, kinematics and the behavior of birds, in which the author of the report considered the following issues: $ the types of birds likely to inhabit Marina del Rey, $ the ability of birds to take off and land, $ soaring conditions upwind and downwind of the proposed building, $ effects on local thermal soaring conditions, and $ changes in flight efficiency due to turbulence. It is our opinion that the minimal changes in the existing wind fields due to the proposed development will result in no significant change to the birds= use of the area. Change of Air Flow Patterns Changes in wind speed and direction patterns are expected in the immediate vicinity of the proposed development. Due to this localized nature, there will be no perceived effect on the general air circulation patterns within Marina del Rey.
December 15, 2006 Mr. Melinkoff Christopher A. Joseph & Associates Page 4 Closing In conclusion, while localized variations in wind speed and direction are likely to occur in Admiralty Park, the proposed Marina del Rey Tower is expected to have minimal effect on wind conditions in the adjacent Basins and the Main Channel, the potential loss of surface winds used by birds and the general air circulation in Marina del Rey. The above opinion is based on the design information of the Marina del Rey Tower, local wind directionality, previous wind studies in the Marina del Rey area, and our experience and engineering judgment. If you have any questions in this regard, please do not hesitate to contact us. Yours very truly, ROWAN WILLIAMS DAVIES & IRWIN Inc. Tahrana Lovlin, P.Eng. Project Engineer Dan Bacon Senior Project Manager / Associate HW/DEB/yio Attach.
FIGURES
SPRING (March, April, May) SUMMER (June, July, August) FALL (September, October, November) WINTER (December, January, February) Directional Distribution of Seasonal Winds (7:00 am - 9:00 pm) Los Angeles International Airport (1947-1990) Figure No. 1 Date: December 1,2006 Marina del Rey Tower, California Project #07-1161
APPENDIX A
Glendale 5 101 405 Los Angeles 10 10 SITE LOCATION 1 90 405 Inglewood 42 110 105 Pacific Ocean 1 91 Long Beach 710 Torrance Legend 110 405 0 1 2 3 4 1 Miles Source: ESRI Data and Maps; Data: June 2006; Author. Christopher A. Joseph & Associates. 0 2 4 6 8 Miles Exhibit 1 Regional Map
La Villa Marina Redwood Ave Carter Ave Yale Ave Stanford Ave Del Rey Ave Glencoe Ave Maxella Ave Burrell St Berkeley Dr Princeton Dr Thatcher Ave Admiralty Park Marina Pointe Dr Admiralty Way 90 PROJECT SITE Bali Way Marina Del Rey Mindanao Way Lincoln Blvd 1 Legend Project Site 0 250 500 750 1000 Feet Fiji Way Source: Christopher A. Joseph & Associates, 2006. Source: ESRI Data and Maps; Date: June 2006; Author: Christopher A. Joseph & Associates. Exhibit 2 Vicinity Map 0 250 500 750 1,000 Feet
Source: Murhpy/Jahn, 2006. 0 25 50 Scale (Feet) 75 100 Figure III-2 West Elevation
Source: Murphy/Jahn Architects, 2006. 0 25 50 75 100 Figure III-3 Feet Building Section
Source: Murphy/Jahn Architects, March 31, 2006. Figure III-4 Proposed Site Plan
APPENDIX B