The information here is correct as of March / April 2016. These roads change pretty quickly, so bear this in mind if relying on this information.
There are three big desert sections when travelling between Tashkent (capital of Uzbekistan) and Aktau (Kazakh port on Caspian Sea), or vice versa. I travelled from East to West, so this information is presented in that direction.
Section 1: Bukhara to Khiva (Uzbekistan)
From Gazli onwards, there is brand new road all the way to the area around Khiva. Full details of this section are on a PDF here: Bukara to Khiva March 2016
Section 2 – Nukus (Uzbekistan) to Beyneu (Kazakhstan)
Road quality is not as good as the earlier section, but is surfaced all the way to the border (very poor surface in places). From Nukus, there are only three water points (also providing shelter in winter). These are:
1. the Bon Voyage truck stop (140km from Nukus)
2. the Al’Yan ‘motel’ at Jasliq (130km from the Bon Voyage) and
3. a small tea house (chaikhana) at Karakalpakiya (140km from Jasliq). This is 20km from the border, where there are several shops and cafes etc.
The road from the border to Beyneu is horrendous (below):
There is around 60km of dirt before things improve (slightly) on the outskirts of town.
A fuller account of this section can be found here.
Section 3 – Beyneu to Aktau
This section is often described in older blogs as ‘the worst road in the world’. This is no longer the case. In April 2016, there was only a total of 5km left unsurfaced; the rest is now good tarmac. A PDF with facilities and locations of water, shelter etc can be found here: Beyneu to Aktau – April 2016
None of these sections are now especially difficult in themselves. But the weather conditions (heavy winds and rain when I crossed, 45C heat in summer, sub-zero in winter) are likely make or break a trip across the desert. Take care out there!