@Essyk, my dear, you, as an individual want the Somalian Somali to leave "Nairobi" because of the social mannerisms they exhibit. You do not like them. Period. Who else does not meet your standards? The Chinese, the Indians, the Europeans, the Kikuyus?
They have the money, from whatever source, but they have the money and the last time I checked, Kenia is a Capitalist state.
Those that have the money have chosen to buy plots in areas they feel comfortable in and invite their respective relatives to come and live with them and hence the overcrowding. "They" could have gone to Nyeri or Kisumu but no, "they" chose Eastleigh et al.
The operative word here is BUY. Naturally, if a Somali or any person for that matter, offers me three times or more the value a "Kenian" would offer, I would close the deal.
At this juncture, I would have expected you to be complaining bitterly against the Immigration department for its failure to prevent the influx and not the "Somali".
Your other complaint is the infrastructure. This is a common phenomenon in urban areas all over Kenia and not just your beloved sections of "Nairobi". In that case, your bile should be directed at the local government and not again at the "Somalis".
"Nairobi" seems to offer a certain attraction to East Africans and that is why I gave you of the rich that I know of personally. The Agikuyu who I know tend to marry several wives and have what I call "city" wives and children as well as a Gishagi wive popularly know as wife of the goats and children.
Fine. KDF plays its part and Somaliland becomes peaceful, naturally, the Somali Somali will want to go "home" if it is attractive enough for them to do so. The Kenyan Somali will definitely want to stay "home", "Nairobi". Will you be the one to decide who stays or who goes?
I would advocate for you to now require the relevant government agencies and departments, just as the KDF has done, to perform their respective duties to avoid a recurrence of the Somali phenomenon for we shall have other communities in East Africa coming into your "Nairobi" whose social structures will not be attractive to you.