Where do people in Netherlands wash their bikes? This would seem to be an absurd question, but I would like to know (especially from the Dutch or people staying in Netherlands) where do they clean their bikes? I am talking about:

a) Cleaning bike that's badly covered in mud / sand.

In Netherlands there are not many trails, but there is a wonderful beach nearby. I would love to ride on the beach but won't because I am staying in an apartment that has an extremely small bathroom and there is no balcony / terrace that I can use. I would not like to choke the bathroom outlet with too much of dust and dirt.

b) During rainy season after a few rides where to rinse the bike with normal clean water? 

My situation: 
I do not have the facility to use a water spray / jet spray that I can for cleaning my bike on the pavement outside my apartment. 

My bikes
I own an MTB currently and am soon planning to buy a nice road bike as well. Despite what bike I own I love it and would like to keep it in the best possible condition. 

People in Netherlands are passionate about biking and often ride good road bikes, and I'm sure the enthusiastic riders would've also definitely have faced such situation while caring for their bikes. 

I am looking for some useful ways of cleaning here.
I use a portable weed sprayer with warm water in it.  Like one of these - Portable Pressure Sprayer.  They aren't high enough pressure to cause problems to bearings and light enough to carry up and down stairs in an apartment building/small enough to store under a kitchen sink.