Your street may differ: each report covers a reservoir or tower and the area it feeds, and higher streets lose water first. What JW's words mean
Day by day
In 2026 so far: 7 days short of water for Constantia Tower, from 189 days with a report; 7 days for Horizon Tower, from 189. A typical supply in the city, the median one (half had fewer), had 4 days.
Each square is a day, as JW reported it for a supply: a reservoir or tower that JW reports on. The number at the right is the month's days short of water.
In 2026 so far, JW reported at least one of Selwyn's 2 supplies short of water on 12 days
3 March 2025 to 29 September 2026, from 497 days with a JW report.
Constantia Tower
In 2026 so far: 7 days short of water, from 189 days with a JW report.
11531short
2025
Mar0
Apr0
May1
Jun0
Jul3
AugNo JW boards, Aug 2025 to Jan 2026
2026
Feb0
Mar0
Apr1
May2
Jun0
Jul3
Aug0
Sep1
Horizon Tower
In 2026 so far: 7 days short of water, from 189 days with a JW report.
11531short
2025
MarNo JW boards this month
Apr1
May1
Jun0
Jul2
AugNo JW boards, Aug 2025 to Jan 2026
2026
Feb0
Mar1
Apr1
May1
Jun0
Jul3
Aug1
Sep0
water as normal
supplying fairly
JW warned
low, or weak in places
short of water
critically low
shut for the night
no JW report
still filling in
JW's reported status of the reservoir or tower, not measured water at taps. Boards from March 2025.
Source: Johannesburg Water's System Update boards and notices, read by us. How this record is made.
Cite this figure
watersearch (2026). “In 2026 so far, JW reported at least one of Selwyn's 2 supplies short of water on 12 days”. Data release 2026-09-29-318d9dca. https://watersearch.co.za/suburb/selwyn#fig-year
The data as a table
Supply
Month
Days reported
Days in record
Adequate or fair
Poor pressure in places, or low
Warning: no water may occur
Poor pressure to no water
Critically low
Overnight closure
Constantia Tower
March 2025
18
29
18
0
0
0
0
0
Constantia Tower
April 2025
22
30
22
0
0
0
0
0
Constantia Tower
May 2025
16
31
15
0
0
1
0
0
Constantia Tower
June 2025
27
30
24
0
0
0
0
3
Constantia Tower
July 2025
17
31
14
0
0
2
1
0
Constantia Tower
August 2025
0
31
0
0
0
0
0
0
Constantia Tower
September 2025
0
30
0
0
0
0
0
0
Constantia Tower
October 2025
0
31
0
0
0
0
0
0
Constantia Tower
November 2025
0
30
0
0
0
0
0
0
Constantia Tower
December 2025
0
31
0
0
0
0
0
0
Constantia Tower
January 2026
0
31
0
0
0
0
0
0
Constantia Tower
February 2026
7
28
7
0
0
0
0
0
Constantia Tower
March 2026
21
31
21
0
0
0
0
0
Constantia Tower
April 2026
30
30
28
0
0
1
0
1
Constantia Tower
May 2026
31
31
26
1
0
1
1
2
Constantia Tower
June 2026
30
30
29
0
0
0
0
1
Constantia Tower
July 2026
31
31
28
0
0
0
3
0
Constantia Tower
August 2026
19
31
19
0
0
0
0
0
Constantia Tower
September 2026
20
29
19
0
0
1
0
0
Horizon Tower
March 2025
0
29
0
0
0
0
0
0
Horizon Tower
April 2025
1
30
0
0
0
0
1
0
Horizon Tower
May 2025
2
31
1
0
0
1
0
0
Horizon Tower
June 2025
4
30
4
0
0
0
0
0
Horizon Tower
July 2025
12
31
10
0
0
2
0
0
Horizon Tower
August 2025
0
31
0
0
0
0
0
0
Horizon Tower
September 2025
0
30
0
0
0
0
0
0
Horizon Tower
October 2025
0
31
0
0
0
0
0
0
Horizon Tower
November 2025
0
30
0
0
0
0
0
0
Horizon Tower
December 2025
0
31
0
0
0
0
0
0
Horizon Tower
January 2026
0
31
0
0
0
0
0
0
Horizon Tower
February 2026
7
28
7
0
0
0
0
0
Horizon Tower
March 2026
21
31
20
0
0
0
1
0
Horizon Tower
April 2026
30
30
29
0
0
0
1
0
Horizon Tower
May 2026
31
31
30
0
0
0
1
0
Horizon Tower
June 2026
30
30
30
0
0
0
0
0
Horizon Tower
July 2026
31
31
28
0
0
0
3
0
Horizon Tower
August 2026
19
31
17
1
0
0
1
0
Horizon Tower
September 2026
20
29
20
0
0
0
0
0
A day counts as short of water when JW's worst report for it that day was “poor pressure to no water” or “critically low”, as happening or expected (expected most often means higher streets). A warning that it may occur does not count.
In short
The latest JW report on this site is from 29 September 2026; the site last read JW's website on 1 October. Constantia Tower and Horizon Tower had water as normal. This year Horizon Tower was short of water on 7 of the 189 days JW reported it. A typical reservoir or tower in the city had 4 such days. On Horizon Tower, half of its last 8 outages lasted at least 25 hours; the longest since March 2025 lasted 47 hours. No JW notice we have read names Horizon Tower.
On JW's list of towers, June 2024, as Selwyn. Source 1 ↗
Outages
JW reported 16 outages on Selwyn's supplies since March 2025. The longest lasted 2.1 days. Every outage, with how long it lasted: Constantia Tower and Horizon Tower.
JW's end dates
No JW notice we have read stated an end time for these supplies. Each end date against what happened: Constantia Tower and Horizon Tower.
Under strain
In 2026 so far, Selwyn had 13 days under strain: days when JW reported any of its supplies low or worse, or warned that higher-lying areas may lose water. This is a wider count than days short of water.
The network is linked. Selwyn draws on all its supplies at once, and when one runs low the others carry more. At such times JW's boards sometimes warn of “poor pressure to no water in higher-lying areas”: under strain, higher streets lose water first. JW does not say which streets those are.
What JW's boards cannot tell you
JW's boards report reservoirs and towers, so some things are not in this record:
Whether water reaches your street or your tap.
Which streets lose water first: JW warns of higher-lying areas but does not name the streets.
Why a supply ran low, unless a JW notice gives a reason.
Pipe bursts, tankers and valve work, which are not on the boards.