Discharges into water and burden on surface water in the Netherlands, 1990, 1995, 1999 and 2000
| Discharges in 2000 | Burden in 2000 | ||||||||
| total | among which | total | of which | ||||||
| indirect | direct | effluents from UWWTPs | sewage system1) | atmospheric deposition | leaching and run-off | ||||
| 1,000 kg | |||||||||
| Total N | 76 200 | 65 900 | 117 000 | 10 400 | 29 000 | 2 290 | 5 260 | 70 000 | |
| Total P | 9 300 | 7 070 | 9 000 | 2 240 | 2 850 | 122 | 3 800 | ||
| Cadmium (Cd) | 1.18 | 0.905 | 0.906 | 0.274 | 0.356 | 0.0664 | 0.0391 | . | |
| Chromium (Cr) | 31 | 25.9 | 11.9 | 5.11 | 5.39 | 0.445 | 0.988 | . | |
| Copper (Cu) | 200 | 155 | 67.5 | 45.9 | 17.6 | 2.01 | 2.04 | . | |
| Mercury (Hg) | 0.739 | 0.699 | 0.184 | 0.0404 | 0.139 | 0.0051 | . | ||
| Lead (Pb) | 137 | 91.5 | 94.9 | 45.8 | 9.22 | 29.2 | 10.7 | . | |
| Nickel (Ni) | 28.5 | 22.2 | 22.8 | 6.29 | 12.5 | 0.888 | 3.1 | . | |
| Zinc (Zn) | 420 | 323 | 261 | 96.8 | 106 | 50 | 8.09 | . | |
| Arsenic (As) | 5.54 | 3.74 | 4.59 | 1.8 | 2.79 | . | . | ||
| Benzene | 132 | 1.89 | 130 | 130 | 0.226 | . | |||
| Benzo(a)pyrene | 0.54 | 0.123 | 0.772 | 0.417 | 0.016 | 0.066 | 0.273 | ||
| Ethylbenzene | 3.82 | 3.64 | 0.912 | 0.184 | 0.73 | . | |||
| Fluoranthene | 2.64 | 0.455 | 5.53 | 2.18 | 0.091 | 0.335 | 2.92 | ||
| PAH (Borneff 6) | 4.08 | 0.819 | 7.05 | 3.26 | 0.189 | 0.401 | 3.2 | ||
| Toluene | 338 | 6.55 | 332 | 332 | 0.393 | . | |||
| Xylenes | 165 | 4.96 | 160 | 160 | 0.248 | . | |||
| Chlorides | 1 589 000 | 84 700 | 1 585 000 | 1 505 000 | 80 500 | ||||
| kg | |||||||||
| 1,2,-Dichloroethane | 1 540 | 78.6 | 1 490 | 1 460 | 31.4 | . | |||
| Hexachlorobutadiene | 0.01 | - | 0.01 | 0.01 | - | - | |||
| 1,1,1,- Trichloroethane | 33.1 | 0.0056 | 33.1 | 33.1 | 0.00033 | . | |||
| Trichloroethene | 848 | 811 | 77.6 | 37.1 | 40.6 | . | |||
| DRINS | 1.1 | 0.001 | 1.1 | 1.1 | - | - | |||
| Source: CCDM (2002). | CBS/ EDC/Oct02 | ||||||||
| 1) The sum of discharges from overflows, rainwater drains and discharges from direct (untreated) sewer systems. Terms and definitions 'discharges into water and burden on surface water' | |||||||||
Developments in the burden on surface water
As a result of wastewater treatment measures and a fall in indirect discharges, the effluents from wastewater treatment plants (UWWTPs) have fallen for most substances. Nevertheless, effluents from UWWTPs still account for a major proportion of the burden on surface water. The effluents are the remainder of indirect discharges after treatment. As a result of reductions in discharges, primarily from business, direct discharges to surface water in the period 1990-2000 fell considerably (see also Discharge Reduction Objectives for Water).
Alongside direct discharges, effluents and discharges from the sewer system, there is also atmospheric deposition on the surface water. Finally, for N and P, run-off and leaching from agricultural land is an important source for the burden on surface water. The relationship between discharges and burdens is discussed elsewhere.
