Rand Water | Integrated Annual Report 2025

INTEGRATED ANNUAL REPO

QUALITY OF WATER SUPPLIED TO CUSTOMERS Rand Water is deeply committed to protect the public and complies with the South African National Standard (SANS) 241 for drinking water quality to ensure the delivery of safe drinking water to Water Services Authorities. This is achieved by implementing stringent water quality specifications against which the company measures itself, assessments and processes throughout the supply chain under Rand Water control. The quality of drinking water delivered to Rand Water customers during this financial year met all contractual and legislated standards and is thus safe for human consumption. All physical, chemical, and biological health-related parameters were compliant to the SANS 241 drinking water quality standard except for residual disinfectant and combined trihalomethanes as a result of changes in raw water quality changes, these were managed adequately and did not pose unacceptable health risks as indicated in the table below. The compliance levels reported are against the excellent water quality requirements of SANS 241:2015 standard.

Table 21: Customer Bulk Water Quality Report

Customer Bulk Distribution water quality report: 21 June 2024 to 20 June 2025 Determinands Measurement Units Risks SANS No of results

Required compliances

Achieved compliances

241:2015 standard limits (1)

to SANS 241:2015 spec (%)

to SANS 241:2015 spec (%)

Microbiological determinands E. coli

(mpn per 100 mL) Acute health Non-detect

15 259 15 259 15 212

99,00% 95.0% 95.0% 99.0% 99.0% 95.0% 95.0% 95.0% 95.0% 95.0% 95.0% 95.0% 95.0% 95.0% 97.0% 97.0% 97.0% 99.0% 99.0% 99.0% 95.0% 95.0% 95.0%

99,89% 97,81% 97,71% 100,00% 100,00% 100,00% 99,55% 100,00% 100,00% 98,28% 99,97% 100,00% 100,00% 100,00% 100,00% 100,00% 100,00% 100,00% 100,00% 100,00% 94,65% 100,00% 100,00%

Total Coliforms

(mpn per 100 mL) Operational

≤ 10

Heterotrophic Plate Count Cryptosporidium spp (2)

(cfu per 1 mL) (org / 10 Litre) (org / 10 Litre)

Operational

≤ 1000

Acute health Non-detect Acute health Non-detect

225 225

Giardia spp (2)

Somatic Coliphages (2)

(count per 10 mL) Operational

Non-detect

1 149

Physical and Aesthetic determinands Colour

(mg / L as Pt-Co) Aesthetic

≤ 15

1 778

Conductivity

(mS / m) (mg / L)

Aesthetic Aesthetic

≤ 170

10 989

Total Dissolved Solids

≤ 1200

1 510

Turbidity Turbidity

(NTU) (NTU)

Operational

≤ 1 ≤ 5

11 464 11 464 11 185

Aesthetic

pH

(pH units)

Operational

≥ 5 to ≤ 9.7

Chemical Properties: Macro determinands Ammonia (mg / L as N)

Aesthetic Aesthetic

≤ 1.5 ≤ 300

10 714

Chloride

(mg / L as Cl) (mg / L as Cl 2 ) (mg / L as Cl 2 ) (mg / L as F) (mg / L as N) (mg / L as N) (mg / L as N) (mg / L as Cl 2 ) (mg / L as Na) (mg / L as SO 4 )

1 347

Free chlorine

Chronic health ≤ 5 Chronic health ≤ 4.1 Chronic health ≤ 1.5

15 346 11 383

Monochloramine

Fluoride

1 343

Nitrate Nitrite

Acute health Acute health Acute health

≤ 11 ≤ 0.9

10 726 10 589 10 467

Combined nitrate plus nitrite (3) Residual disinfectant (4)

≤ 1

Operational

≥ (0.1 and 0.2)

15 346

Sodium Sulphate

Aesthetic Aesthetic

≤ 200 ≤ 250

1 366 1 385

147

Rand Water | Integrated Annual Report 2025