According to Mauritius's Environmental Laws, there are a few standards for the sewage and industrial effluent discharges to land, surface water and oceans:
Effluent Discharge Permit Regulations
Government Notice No. 43 of 2003
THE ENVIRONMENT PROTECTION ACT 2002
Regulations made by the Minister under Section 96 of the Environment Protection Act 2002
| Parameter |
Unit | Maximum permissible limit second schedule |
Maximum permissible limit second schedule |
Maximum permissible limit third schedule |
| Land/ Underground | Surface water courses | Industry within 200meters of High water mark | ||
| Total coliforms | MPN per 100 ml | - | 400 | <400 |
| E. Coli | MPN per 100 ml | <1000 | <200 | <200 |
| Free Chlorine | mg/l | - | 0.5 | 0.5 |
| Total Suspended Solids (TSS) | mg/l | 45 | 35 | 35 |
| Reactive Phosphorus | mg/l | 10 | 1 | 1 |
| Color | - | Not objectionable | Not objectionable | Not objectionable |
| Temperature | degree C | 40 | 40 | 40 |
| pH | - | 5-9 | 5-9 | 5-9 |
| Chemical Oxygen Demand (COD) | mg/l | 120 | 120 | 120 |
| Biochemical Oxygen Demand (BOD5) | mg/l | 40 | 40 | 40 |
| Chloride | mg/l | 750 | 750 | 1500 |
| Sulphate | mg/l | 750 | 750 | 1500 |
| Sulphide | mg/l | 0.002 | 0.002 | 0.002 |
| Ammoniacal Nitrogen | mg/l | 1 | 1 | 1 |
| Nitrate as N | mg/l | 10 | 10 | 10 |
| Total Kjeldahl Nitrogen (TKN) | mg/l | 25 | 25 | 25 |
| Nitrite as N | mg/l | 1 | 1 | 1 |
| Aluminium | mg/l | 5 | 5 | 5 |
| Arsenic | mg/l | 0.1 | 0.1 | 0.1 |
| Beryllium | mg/l | 0.1 | 0.1 | 0.1 |
| Boron | mg/l | 0.75 | 0.75 | 0.75 |
| Cadmium | mg/l | 0.01 | 0.01 | 0.01 |
| Cobalt | mg/l | 0.05 | 0.05 | 0.05 |
| Copper | mg/l | 0.5 | 0.5 | 0.5 |
| Iron | mg/l | 2.0 | 2.0 | 2.0 |
| Lead | mg/l | 0.05 | 0.05 | 0.05 |
| Lithium | mg/l | 2.5 | 2.5 | 2.5 |
| Manganese | mg/l | 0.2 | 0.2 | 0.2 |
| Mercury | mg/l | 0.005 | 0.005 | 0.005 |
| Molybdenum | mg/l | 0.01 | 0.01 | 0.01 |
| Nickel | mg/l | 0.1 | 0.1 | 0.1 |
| Selenium | mg/l | 0.02 | 0.02 | 0.02 |
| Sodium | mg/l | 200 | 200 | 200 |
| Total Chromium | mg/l | 0.05 | 0.05 | 0.05 |
| Vanadium | mg/l | 0.1 | 0.1 | 0.1 |
| Zinc | mg/l | 2 | 2 | 2 |
| Oil & Grease | mg/l | 10 | 10 | 10 |
| Total Pesticides | mg/l | 0.025 | 0.025 | 0.025 |
| Total organic halides | mg/l | 1 | 1 | 1 |
| Cyanide (as CN -) or Free cyanide | mg/l | 0.1 | 0.1 | 0.1 |
| Phenols | mg/l | 0.5 | 0.5 | 0.5 |
| Detergents (as LAS*) * Linear Alkylate Sulphonate |
mg/l | 15 | 15 | 15 |
Standards for effluent discharge into the Ocean Regulations
Government Notice No 45 of 2003
THE ENVIRONMENT PROTECTION ACT 2002
Regulations made by the Minister under sections 39 and 96
of the Environment Protection Act 2002
| Parameter |
Unit | Permissible limits |
| Temperature
pH Floatables |
oC
- mm |
40
5 - 9 6 |
| Biochemical Oxygen Demand (BOD5)
Chemical Oxygen Demand (COD) Suspended Solids |
mg/l
mg/l mg/l |
250
750 300 |
| Cadmium
Chromium (VI) Chromium, Total Cyanides (as CN-) Lead Nickel Zinc Total Mercury Arsenic |
µg/l µg/l µg/l µg/l mg/l mg/l mg/l µg/l µg/l |
20
100 500 100 2 2 2 10 200 |
| Total pesticides
Oil & Grease |
mg/l
mg/l |
1
20 |
Standards of effluent for use in Irrigation Regulations
Government Notice No.46 of 2003.
THE ENVIRONMENT PROTECTION ACT 2002
Regulations made by the Minister under sections 39 and 96 of the Environment
Protection Act 2002
| List | Parameter (1) |
Unit |
Standards |
| A | pH
Colour |
-
- |
5 - 9
not objectionable |
| B | Biochemical Oxygen Demand (BOD5)
Chemical Oxygen Demand (COD) Suspended Solids Chloride Sulphate Nitrate N Total Dissolved Solids Sodium Adsorption Ratio (SAR) |
mg/l
mg/l mg/l mg/l mg/l mg/l mg/l - |
40
120 45 250 500 20 2000 < 6 |
| C | Aluminium
Arsenic Beryllium Boron Cadmium Chromate chromium Cobalt Copper Fluorine Iron Lead Lithium Manganese Molybdenum Nickel Mercury Selenium Vanadium Zinc |
mg/l
mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l |
5
0.10 0.10 0.75 0.01 0.10 0.05 0.20 1 5 2 2.5 0.2 0.01 0.20 0.02 0.02 0.10 2 |
| D | Total Pesticides
Oil & Grease Detergents |
mg/l
mg/l mg/l |
0.025 10 5 |
| E | Faecal coliforms (2)
Intestinal nematodes (2) |
MPN per 100 ml
Arithmetic mean no. of eggs per litre |
1000 (3)
< 1 |
Notes:
(a) 1 A 95% compliance limit will be accepted based on the series of samples taken in a year
(b) 2 Prohibited for crops to be eaten raw
(c)3 200 faecal coliforms MPN/100 ml for public lawns such as hotel lawns, with which the public may have direct contact.
Download the Mauritius Environmental Laws related to Effluent Discharge Standards documents in pdf format:
1. 
Mauritius:
Guidelines for irrigation water quality (G.N. No. 617 of 1999). (File
Size: 35 Kb)
2. 
Environment
Protection (Drinking Water Standards) Regulations 1996 (G.N. No. 55 of 1996).
(File Size: 47 Kb)
3.
Waste
Water (Standards for Discharge of Industrial Effluent into a Waste Water
System) Regulations 2004 (G.N. No. 182 of 2004). (File Size: 106 Kb)
4.
Environment
Protection (Standards for effluent discharge) Regulations 2003 (G.N. No.
44 of 2003). (File Size: 95 Kb)
5.
Mauritius
Environment Protection (Standards for effluent discharge into the ocean)
Regulations 2003 (G.N. No. 45 of 2003). (File Size: 31 Kb)
Related links:
1. Mauritius Ministry of Environment http://www.gov.mu/portal/site/menvsite/menuitem.0eab364c8ebfb2fc62aee21d48a521ca/