Urinating in an open area: [1]
The above laws of distancing oneself from others only applies to a bowel movement, however when one needs to urinate, he may do so even in front of others and during the day[2], if this is required. The reason for this is because withholding the urge to urinate is dangerous [and can cause one to become sterile[3]]. Therefore it is forbidden for one to act with modesty and delay urinating [in order to find a private area] if he needs to do so.[4] Nevertheless, one should go to the side [of the area that he is in] to relieve himself.[5]
[1] Basra 3:5; Kama 3:18; M”A 3:12; Gemara Bechoros 44a; So rules also: Kitzur SHU”A 4:2; Ben Ish Chaiy Vayeitzei; ; M:B 3:22; Sefer Shemiras Haguf Vihanefesh [Lerner] 58:2
Siddur Seder Netilah: “One may urinate in public due to worry of danger. Nevertheless one should do it on the side”
[2] Basra ibid; In Kama the order is “even during the day in front of others”.
[3] Basra 3:5; see also Kama 3:24 and Basra 3:11
[4] Basra 3:5; Omitted in Kama ibid or Siddur ibid. [There Admur simply writes it is permitted to urinate in public and not that one must do so.] Vetzaruch Iyun Gadol as in Basra 3:11 Admur rules one may withhold himself to find a private area, and it is implied from there that it refers to both urine and bowel movement. Thus one must differentiate and say that the ruling there only refers to a bowel movement. Alternatively it refers to withholding urine until one reaches a side area in public, as Admur writes here. Alternatively perhaps here it is referring to someone who has a very strong urge to urinate and hence holding himself back has a high chance of causing him to be sterile. Perhaps this can be deduced from the seemingly superfluous words “if he has to” that Admur adds here, that it is coming to say the person has a strong urge to urinate. However there it refers to a minor urge, such as a person who can hold it in for up to a Parsa, in which case we allow a person to delay his needs for privacy. Vetzaruch Iyun.
[5] Basra 3:5 and Siddur; In Kama ibid mention of going to the side is only made regarding a woman, while in Basra it mentions it both regarding a man and woman.
May one urinate in front of others if he has no choice? Yes. One may urinate even in front of a woman. [Chayeh Adam 3:1 brought in Kaf Hachaim 3:36]