After originating in Uttarakhand, the Yamuna enters Himachal and collects water from numerous Himalayan rivers that are inundated with fresh rainwater^[1]

¶ Hathni Kund Barrage^[2][3]

Yamuna eventually passes through Hathni Kund Barrage, in Haryana's Yamuna Nagar District, which further releases water into Delhi.

Hathni Kund Barrage is a not reservoir but regulates water, has three branches:

1. Western Yamuna Canal (WYC)
   • Towards Haryana
   • Capacity 18000 cusecs^[9]
2. Eastern Yamuna Canal (EYC)
   • Towards UP
   • Capacity 7000 cusecs^[9]
3. Yamuna Main River
   • Towards Delhi

Usually water is released in all 3 branches from barrage

 

¶ Delhi Floods 2023^[2][3]

AAP position:

1. No/Negligible water released towards Western Yamuna Canal(towards Haryana) from 9th July to 13th July 2023 despite capacity of 18000 cusecs
2. No/Negligible water released towards Eastern Yamuna Canal(towards UP) from 9th July to 13th July 2023 despite capacity of 7000 cusecs^[9]
3. Most water was released towards Delhi, resulting in flooding of City

 

From 9-13 July 2023

• Over 2 lakh cusecs Water discharge started on 9th July 2023
• Peak of 3.58 lakh cusecs Water was discharged on 11th July 2023

13th July 2023^[4]

As per Daily Water release data on official website: 

• Only 1.51 mcum water in total was diverted to Haryana & UP branches
• 99.42% water was released towards Delhi

Only after Delhi Govt exposed this via a Press Conference and questioned this distribution, water was released into EYC and WYC^[6]

Even Home Minister Amit Shah's intervention was sought on Hathni Kund by CM Arvind Kejriwal on 13th July but to not much visible effect^[7]

 

14th July 2023^[4]

As per Daily Water release data on official website: 

• 15.48 mcum water in total was diverted to Haryana & UP branches
• Only 83.47% water was released toward Delhi

Water towards Haryana/UP:

10 times more water in absolute quantity

29 time more water in terms of %share

Video Proofs too comparing water flows^[5]

 

 

 

 

 

 

 

15th July 2023^[4]

As per Daily Water release data on official website: 

• 16.78 mcum water in total was diverted to Haryana & UP branches
• Only 77.79% water was released toward Delhi

Water towards Haryana/UP:

11 times more water in absolute quantity

38 times more water in terms of %share

 

 

 

Other side Position^[9]:

CWC has issued a guideline that if the flow of water in Yamuna raises above 1 lakh cusecs of water, which is the threshold mark, then the gates of two canals should be closed.

Could the Hathni Kund water regulator have regulated the supply better?

Eventually the point to ponder is if it's the peak of water discharge matters or the peak of average discharge over days which matters?

If the regulator has Zero control, then it would be futile to have a regulator built-up. Regulars have a role but only to a limited extent and management of that limited control is being debated here

 

References:
[1] https://en.wikipedia.org/wiki/Yamuna

[2] https://twitter.com/AamAadmiParty/status/1680094851985973249

[3] https://twitter.com/attorneybharti/status/1679869133209604097

[4] http://hathnikundscada.com/

[5] https://twitter.com/AamAadmiParty/status/1679903301138276358

[6] https://twitter.com/AamAadmiParty/status/1679767762288414720

[7] https://www.hindustantimes.com/cities/delhi-news/delhi-cm-seeks-home-minister-s-help-as-yamuna-water-level-rises-bjp-claims-insufficient-flood-mitigation-measures-101689186231613.html

[8] https://timesofindia.indiatimes.com/city/delhi/its-not-just-haryana-heres-why-delhi-is-flooded-despite-little-rain-in-4-days/articleshow/101741441.cms?from=mdr

[9] https://www.republicworld.com/india-news/general-news/delhi-floods-how-hathnikund-barrage-works-aaps-allegation-falls-flat-articleshow.html