I will make a brief presentation tonight at Culver City Council about the OAPM. The Environmental Assessment (EA) was a difficult document to parse, made even more so by the omission of key information by the FAA and a lack of specificity in the visual figures. Part of that deficiency was made up at the public meeting- the coordinates of the flight paths were shared. This allowed me to do some mapping. Here is some of the information I will be presenting:
1.) The new RNAV arrival flight path is pushed farther North and the RNAV ( which represents the path of controlled descent ) exits east of the city (at DAHJR) compared to where it previously exited at SMO. The extended RNAV will reduce some of the lower flights that were occurring over Culver City and the Optimised Profile Descent(OPD) will hopefully keep the airplanes in a more clean noise profile. An additional RNP will probably help concentrate a narrower flight path.
2.) Google Map of the new flight path ( zoomable)
[The FAA changed the CLIFY location. I removed the comments that have been effected by this change. edited- 7/3/2015]
Conclusion: The new flight paths provide some relief to the residents of Carlson Park and Blair Hills but now increase impacts to Downtown, Lucerne-Higuera and the Hayden Tract. Additionally the McManus area will be experiencing more noise than before as the path is closer, the planes will be at a lower height then they were at Carlson Park, and some of the noise-making descent activities may be happening later.
3.) The Noise data the FAA presented is somewhat confusing and there is a few points of question about it. I have captured a portion of the data from the documents and remapped it in an zoomable format.
a.) Here is a map of the overall db DNL levels using the proposed action. The dB represents just the noise from airplanes and doesn’t take into account any other ambient noises:
Conclusion: At an average of 43-44 dB DNL, we are the below 45dB DNL which is below the threshold of consideration for the the EA. Parts of Culver City are better than our neighbors to the South and East. North of us is still quieter.
b.) Here is the map of the change in dB DNL (comparing the proposed action to they way it is now):
Conclusion: The area away from the new paths will be quieter, the areas near/under will be noisier. According to the FAA criteria the noise difference will not be significant. A dB DNL is difficult to subjectivify as we hear noise on a per plane basis – DNL is an aggregate.
The FAA didn’t release all the noise data. To evaluate the noise impacts, as well as the study methodology in regards to noise, they need to release the additional data. I requested it and they expressed to me that they weren’t sure if they should release as a Freedom of Information Act request, or as part of the EA.