Regarding the Zkan Aharon of Karlin I mentioned, I found the responsum see the below link:
http://hebrewbooks.org/pdfpager.aspx?req=835&st=&pgnum=50
Read how he describes the situation of the Delasos. He actually applied every Kulah possible, the structure, the technical issue of the Gov not allowing the dlsos to be closed etc…
This in sync with his shitah and many others, that when it comes to Eruvin you should try to apply any Shitah to enable its structure – you do not look for Chumrahs (Halacha Kdivrei Hamekil). See his reponsum in Shu”T Chelkos Yaakov of Rav Breish, regarding the Eruv in Antrewp