Aerial Taps

[IceVol]

So I'm fresh out of school and learning the transmission trade. My boss is on vacation. I'd like to come up with a solution before he gets back. I've been working on a project where a 115KV line on H structures must go under a 161 KV line and then over a bridge at a 90 degree angle and 40' higher than the ground the tower will built on. I have never heard of or seen a situation similar. The current configuration is two dead ends at right angles that are aerially taped, but the massive bridge does not currently exist. I must significantly raise one set of the towers. To get the line over this new bridge I have to figure out a way to get one section low and one high, but the difference is 40'! Has anyone heard of a 40' tap? How do I figure out if this is ok? I can't find regulations specifically concerning taps in REA or TVA. My concern is adding a significant load to the insulator on the top part of the tower. I believe blow out would not be a factor if there is very little slack, but that adds quite a load. Is there another solution? Maybe eliminate the aerial tap configuration and jumper 40' up a new tower somehow? I would simply like someone to show me a similar problem and how it was solved. Drawings would be fantastic. Thanks
See str. 5803 and 5804 in the attached drawing

 

[rterickson]

If there's no limitation on how tall Str. 5804 can be, I would consider running pipe bus on post insulators to make up your verical height difference. See photo attached of a similar installation. It will be a pretty heavy load at the top.

At first I thought about setting 5804 at a 45-degree angle spanning the east-west portion of the circuit, but you are awefully close to the railroad track already.