Nitrogen and phosphorus balances for fresh surface water in the Netherlands, 1986-2001

Emissions of nitrogen and phosphorus fell considerably between 1986 and 2001. The accumulation of these substances in the environment does not reflect this fall since it is, to a significant extent, determined by precipitation and river flows.

	Inflow1)
	1986	1990	1995	1999	2000	2001
	million kg N
Total	714	533	570	487	432	473
Transboundary rivers	540	362	425	349	312	354
Discharges
- industry	23	18	7	7	6	6
- households	36	36	30	24	23	23
- agriculture and horticulture2)	10	9	6	6	6	5
Agricultural land3)	86	86	86	86	70	70
Other land	4	4	4	4	4	4
Deposition4)	15	18	12	11	11	11
	million kg P
Total	78	47	36	35	26	20
Transboundary rivers	46	20	22	23	17	12
Discharges
- industry	15	16	4	4	2	1
- households	11	4	3	2	2	2
- agriculture and horticulture2)	1	1	0	0	0	0
Agricultural land3)	5	5	5	5	4	4
Other land	1	1	1	1	1	1
Deposition	0	0	0	0	0	0
Source: CBS ().	CBS/EDC/Sep03/0194
1) Excludes discharges to the sea. 2) Direct emissions from fertiliser to ditches and discharges into drainage water from horticulture under glass. 3) Using new calculation method from 2000 onwards. In time, the years in the history will be recalculated using a comparable method. As a result, the trend shift shown at present will be eliminated. 4) Based on a freshwater surface area of 0.39 million hectares and average wet and dry deposition of 29 kg N/ha in 2001.

	Outflow1)
	1986	1990	1995	1999	2000	2001
	million kg N
Total	714	533	570	487	432	473
To the sea	550	343	551	330	339	360
Dredging sludge	7	6	3	3	3	3
Accumulation	157	184	16	154	90	110
	million kg P
Total	78	47	36	35	26	20
To the sea	42	23	32	18	18	13
Dredging sludge	6	5	3	3	3	2
Accumulation	30	19	1	14	5	5
Source: CBS ().	CBS/EDC/Sep03/0194
1) Excludes discharges to the sea. 2) Direct emissions from fertiliser to ditches and discharges into drainage water from horticulture under glass. 3) Using new calculation method from 2000 onwards. In time, the years in the history will be recalculated using a comparable method. As a result, the trend shift shown at present will be eliminated. 4) Based on a freshwater surface area of 0.39 million hectares and average wet and dry deposition of 29 kg N/ha in 2001.

Developments in discharges to surface water

Discharges to surface water fell considerably between 1986 and 2001: discharges of nitrogen by approximately 50% and discharges of phosphorus by approximately 85%. The reduction from industry was approximately 75% for nitrogen and 90% for phosphorus due to intensive clean-up operations and modified production processes. The fall for households of 35% for nitrogen and 80% for phosphorus is mainly the result of alterations to urban wastewater treatment plants for nitrogen and phosphate removal and the introduction of phosphate-free detergents.

Note on accumulation

Changes in emissions are not always reflected in the accumulation figure. The inflow and outflow via rivers is largely determined by the weather. The low accumulation level in 1995, for example, is partly a result of heavy rain and the resulting higher flow rate in 1995.

Policy objective

In order to comply with the European Nitrate Directive, run-off of nutrients from agriculture must be reduced. Stricter legislation, including the Mineral Accounting System (MINAS), is intended to bring about a further reduction in the surpluses from agriculture.

• Discussion of MINAS and the European Nitrate Directive

Technical note

New calculation method used from 2000 onwards. In time, the years in the history will be recalculated using a comparable method. As a result, the trend shift shown at present will be eliminated. More information about the background to the calculation can be found on the Datawarehouse Emissieregistratie.

References

• CBS (2003). Statline. Stikstof en fosfor in Nederland. Statistics Netherlands, Voorburg/Heerlen.
• CCDM (2003). Emissiemonitor. Jaarcijfers 2001 en ramingen 2002. Datawarehouse-Emissieregistratie. Coördinatiecommissie Doelgroepmonitoring, The Hague.
• OSPAR Commission (2002). Annual report on riverine inputs and direct discharges to Convention waters during the year 2001 by the Netherlands. OSPAR, London.

Relevant sections and indicators in the Environmental Data Compendium

• Environmental pressure in the Netherlands, Eutrophication theme: introduction and policy
• Environmental pressure in the Netherlands, Eutrophication theme: introduction and policy
• Eutrophying emissions in the Netherlands, 1980-2001 (page is not available yet)
• Eutrophying emissions to water, 1990-2001
• Guide to 'Impact of environmental pressure on nature' section , with a reference to four indicators about the impact of acidification and eutrophication on nature.

Relevant information outside of the Environmental Data Compendium

• More information about mineral surpluses can be found in Mineralen in de landbouw, 1999 - 2002* (CBS, 2003).
• Recent emission data and descriptions of the calculation methods used (meta-information) can be viewed in detail on the Data Warehouse of the 'Emissieregistratie' website.
• Emission data can also be found on Statline of Statistics Netherlands.