Sequential NW deflection of Sutlej is demonstrated by a sequence of westward shifting abandoned channels of Sutlej, as shown on a map of the Vedic Sutlej joining Vedic River Sarasvati at Shatrana as a tributary.
The authors underscore the important drainage divide separating the Sirsa and Jhajara drainage networks. Remarkable river deflections are aligned linearly over tens of kilometers in a zone about 10 km. south of the HFT.
In a fascinating analytical framework using structural and geomorphological approaches, the authors postulate "the formation of an incipient mountain front that is evolving ahead of the HFT and the outermost Siwalik hills."
I suggest that this formation of the incipient mountain front is exemplified by the deflection, by a virtual U-turn of Sutlej River at Ropar (Rupnagar) during the historical periods.
The crux of the geomorpholocal challenge is to date this deflection of Sutlej.
The study notes that the ongoing collision of the Indian plate with the Eurasian plate has resulted in the southward migration of the Himalayan front and associated landforms with time.
The location of the Pinjaur dun may be seen in Fig. 1B.
Fig. 1. (A) Map showing the regional geology of the area; (B) Map of the geomorphic setting of the study area which lies on the margin of the Nahan salient. a-Chandigarh, b-Pinjaur, c-Kalka, d-Baddi, e-Ropar (Rupnagar), f-Kurali, g-Nahan, h-Paonta Sahib, 1-Sutlej River exit, 2-Ghaggar River exit, 3-Markanda River exit, 4-Yamuna River exit. (C) Map of structures and mountain fronts present in the study area.
Fig. 2(B) shows the Tilt direction of Mountain Fronts 1A and 2 in relation to the Sutlej River deflection in the context of E-W trending HFT.
Noting that the faults and related structures in the area are active, it can be suggested that the activity of the Sirsa fault together with the tilts caused by Mountain Fronts 1A and 2 in a series of seismotectonic events caused the virtual U-turn deflection of Sutlej River at Ropar (Rupnagar) over an extended period of time. There are signature markers available in the nature of scores of naiwals recognized by the palaeo-channels between Sutlej River at Ropar and Ghaggar River. It is clear from the presence of a significant clustering of archaeological settlements that these palaeo-channels splintering out, south of Ropar, of the Sulej River would have served as navigable channels of Himalayan glacier waters, for the people of the settlements. In this scenario, Sutlej River would have been, PRIOR TO THE DEFLECTION, a tributary of Ghaggar River flowing down south from Ropar to Shatrana. This may explain the ground truth of the width of the palaeochannel complex at Shatrana to be a significant width of 20 kms.
A drainage divide of Kalka surface separates the Sirsa and Jhajara River networks. Sirsa river drains into the Sutlej River. Jhajara river drains into the Ghaggar River.
The authors surmise that the drainage divide resulted probably by the upliftment of the outermost Siwalik hills in front of the Kalka surface. This uplift forced the Sirsa River to flow toward the NW and the Jhajara River toward the SE.
This is demonstrated in the Map (Fig. 5) showing the flow of Sutlej River along a NW-SE lineament (marked 1).
Fig. 5 (A) Map showing river anomalies and possible incipient structures in the Indo-Gangetic plains, Sutlej River flowing along a NW-SE lineament (marked 1). Streams draining outermost Siwalik hills between the Sutlej and Ghaggar Rivers take a sudden northwestward bend after initially flowing toward the SW for some distance (shaded region). The incipient structure identified in the Indo-Gangetic plains probably meet the HFT on the southeastern bank of the Ghaggar River...(B) IRS LISS III imagery showing lineament along which the Sutlej River flows after debouching into the plains. Note that just befor flowing along this lineament the flow direction of the Sutlej River is SW and flow direction becomes NW when the river follows the lineament.
This is the geomorphological explanation for the 90-degree turn of Ropar following the lineament.
Fig. 5A, B demonstrate the fact that Sutlej flowing adjacent to the outermost Siwalik hills shows a remarkable deflection toward the NW after flowing some distance to SW.
Source: Singh, Vimal, SK Tandon, 2008, The Pinjaur dun (intermontane longitudinal valley) and associated active mountain fronts, NW Himalaya: tectonic geomorphology and morphotectonic evolution, Geomorphology 102, 376-384
That there are archaeological settlements of Sarasvati-Sindhu civilization in this SW flow of Sutlej River are the definitive indicators that Sutlej River was flowing SW during the mature phases of the archaeological settlements of the civilization.
Such settlements south of Ropar along the Sutlej River as a tributary of Sarasvati (Ghaggar-Drishadvati) River are: Kunal, Banawali, Rakhikgarhi, Kalibangan as may be seen from the following map and the sites marked between Ropar and Shatrana along the reconstructed palaeochannels using Optical (IRS P6) and SAR (Radarsat) images.
The evidence provided validate the possible reconstruction of the palaeochannels along archaeological settlements which were demonstrably involved in maritime trade. An archaeological artifact attesting to this trade is the presence of cylinder seal in Kalibangan which is characteristics of Mesopotamian/Sumer contact areas. Another indicator of significance is the arcaheological site record of a tectonic event dated to ca. 2600 BCE at Kalibangan: B. B. Lal, former DG of ASI writes,"Kalibangan in Rajasthan ... has also shown that there occurred an earthquake around 2600 BC, which brought to an end the Early Indus settlement at the site." ( B.B. Lal 1984. The earliest Datable Earthquake in India, Science Age (October 1984), Bombay: Nehru Centre).
See: http://bharatkalyan97.blogspot.in/2013/01/incisions-of-sutlej-and-90-degree-turn.html
A canal carrying industrial effluents merges with the river Sutlej near Ropar international wetland http://lite.epaper.timesofindia.com/mobile.aspx?article=yes&pageid=7§id=edid=&edlabel=TOIPU&mydateHid=24-08-2009&pubname=&edname=&articleid=Ar00700&publabel=TOI 
Hill erosion near river Sutlej, Ropar. Ropar is the location where River Sutlej takes a 90 degree turn weswards to join the River Sindhu (Indus). 
Hill view near River Sutlej. In summary, a possible sequential NW deflection of Sutlej can be demonstrated by a sequence of westward shifting abandoned channels of Sutlej, as surmised in the following map of the Vedic Sutlej joining as a tributary to Vedic River Sarasvati:
That there are NO archaeological sites along the present Sutlej until it joins the Panjnad and Sindhu rivers in Bahawalpur Province, Cholistan is also a telling evidence that the present Sutlej NW flow is an event closely intertwined with the mature periods of Sarasvati-Sindhu (Hindu) Civilization evidenced by over 80% of archaeological settlements on the Sarasvati River Basin.
The unresolved task is to date the dates of deflections of Palaeoyamuna and Palaeosutlej abandoning Vedic River Sarasvati, thus denying Sarasvati of perennial flows of glacial waters.
S. Kalyanaraman
Sarasvati Research Center
May 18, 2015