Hilsa in context: Street-network sprawl trends

The chart above shows SNDi trends for new street additions (left panel) and the entire network (right panel), with Hilsa plotted against Bihar and India. The SNDi of new construction in Hilsa peaked in 1976-1990, compared to Bihar which followed a zig-zag trend with an overall increase and India which followed a zig-zag trend with an overall increase. Most recently, Hilsa's incremental SNDi fell from 4.56 to 3.1 between 1991-2005 and 2006-2020. In terms of the aggregate network, Hilsa ranked 149th out of 264 cities in Bihar and 1417th out of 1868 in India as of 2020.

Rankings go from most connected to most disconnected — rank 1 is the most connected.

What about similarly populated cities?

• Lingasugur, India
• Machakos, Kenya
• Alafaya, United States
• Mankweng, South Africa
• Abu Bisht, Egypt
• Yutai, China

In new street additions, Hilsa built increasingly disconnected streets from 1975 through 1976-1990, then improved, while Lingasugur built increasingly connected streets from 1975 through 1976-1990, then shifted to more disconnected patterns and Mankweng fluctuated in its street-construction patterns. For the full network, Hilsa grew more disconnected from 1975 through 1976-1990, then improved, while Lingasugur became more connected from 1975 through 1976-1990, then grew more sprawly from 1976-1990 onwards and Mankweng became progressively more disconnected. Notably, Hilsa had a more connected network than Lingasugur in 1975 but the two have since reversed their relative ranking.