Deskew pdf file

Will this work for you? The whole map was slightly rotated clockwise, cropped, and scaled to fit the original map size

It looks like the city may be laid out across two different US land survey sections and that is what is causing the streets in the lower part to still be at a small angle relative to the main part of the map.

 

Used a free program called GIMP (https://www.gimp.org/) to open the PDF file, make the edits, and exported as a PDF. The file was over 8 MB. I opened it in Adobe Acrobat (not the free reader), optimized, and saved it as the much smaller version file.