When I got to the garden one day last week here's the scene I found:
A power line runs through the forest just behind our allotment, and one of the power towers is just off our back border. The city recently began renovating the towers, i.e. cleaning, sanding, and repainting them, for the first time in almost 50 years as my garden neighbors reported. The first ominous sign that our tower was also up for maintenance was the removal of all trees, shrubs, and underbrush within meters of the tower. Before they did this, it looked like this:
But what I was really worried about was possible damage to the garden. I'd already watched them working on the next tower down, further away from the allotments. It had looked like they were sand-blasting, causing large clouds of debris and hours of noise. But as I was standing dismayed in the garden surveying the number of trees and shrubs that had been removed just outside of our lot, the foreman of the maintenance crew approached and explained that they would do all they could to not damage the garden, including covering everything with protective sheets and tarps, and that the workers would all use umbrellas to catch falling debris. Also, in our case they would forgo sand-blasting, instead scraping the decades of moss and dirt off by hand.
And indeed that's what they did. Here they are working on the tower with upside-down umbrellas: