The share of Poland in the phosphorus pollution status of Baltic Sea in the light of HELCOM PLC research

Baltic Sea Sub-basin	MAI^#	P input 2022	Statistical uncertainty 2022	P input including stat. uncert. 2022	Exceedance of MAI in 2022	Input 2022 including stat. uncertainty % MAI	Classification of achieved reduction
Baltic Sea Sub-basin	t year⁻¹						Classification of achieved reduction
Bothnian Bay (BOB)	2 675	2 350	149	2 499		93
Bothnian Sea (BOS)	2 773	2 149	106	2 255		81
Baltic Proper (BAP)	7 360	12 386	807	13 193	5 833	179
Gulf of Finland (GUF	3 600	4 242	723	4 965	1 365	138
Gulf of Riga (GUR)	2 020	1 903	234	2 138	118	106
Danish Straits (DS)	1 601	1 148	57	1 205		75
Kattegat (KAT)	1 687	1 360	67	1 427		85
Baltic Sea (BAS)	21 716	24 958	1 259	26 217	4 501	121

# As adopted by the 2013 HELCOM Copenhagen Ministerial Meeting (HELCOM, 2013) and in BSAP update 2021 (HELCOM 2021). The table also contains data on statistical uncertainty, the remaining reduction needed to reach MAI and inputs in 2022, including statistical uncertainty in percentages of MAI. Classification of achieving MAI is given in colours: green = MAI fulfilled, yellow = fulfilment is not determined due to statistical uncertainty, and red = MAI not fulfilled. NOTE: For consistency with MAI no rounding (to tenth, hundreds or thousands) has been performed in the indicator.

Source: Inputs of nutrients … 1995–2022

Significant reductions of total annual inputs of phosphorus achieved in 2022 (in %) since the reference period 1997–2003 (blue arrow) and recent changes (red arrow)
where: recent changes are significant changes since last breakpoint of the timeseries. The arrows indicate decreasing (↓) inputs, and only significant changes are shown.
Source: Svendsen et al., 2024

Actual total waterborne annual input of phosphorus (TP) to the Baltic Sea and sub-basins from 1995 to 2022 (tons per year).
BAS – Baltic Sea, BOB – Bothnian Bay, BOS – Bothnian Sea, BAP – Baltic Proper, GUF – Gulf of Finland, GUR – Gulf of Riga, DS – Danish Straits, KAT – Kattegat. The normalized total annual inputs of phosphorus are given as a black line. The trend line for normalized total phosphorus is given as a green line with markers. In cases when a break point divides the trend into two parts, the second part (called trend 2) is shown by a green line without marker. In cases with two breaks points the third part (called trend 3) is indicated as a purple line. (Solid trend line shows statistically significant trend and dotted line no statistically significant trend). The MAI as adopted by the 2013 HELCOM Copenhagen Ministerial Meeting (HELCOM 2013) is shown as the bold dotted blue line.
Source: Svendsen et al., 2024

Table 2.

Years with the statistically identified breakpoints in trend lines of total phosphorus TP) inputs to the Baltic Sea and its sub-basins during 1995–2022.

	Breakpoints	Change [%] since reference period	Change [%] after last breakpoint
Bothnian Bay		−18	n.r.
Bothnian Sea		−23	n.r.
Baltic Proper		−26	n.r.
Gulf of Finland	2012	−48	-
Gulf of Riga		−32	n.r.
Danish Straits	2000	−22	−17
Kattegat		−20	n.r.
Baltic Sea		−32	n.r.

[i] “-” no significant trend; n.r. – not relevant as there is no break point

[ii] Source: Svendsen et al., 2024

Table 3.

Country – Baltic Sea basin total phosphorus input ceilings in tons per year (2021).

Country	Baltic Sea basin^#
Country	BOB	BOS	BAP	GUF	GUR	DS	KAT
Germany (DE)	-	-	203	-	-	401
Denmark (DK)	-	-	21	-	-	979	815
Estonia (EE)	-	-	9	22	185	-	-
Finland (FI)	1683	1246		315	-	-	-
Lithuania (LT)	-	-	703	-	175	-	-
Latvia (LV)	-	-	167	-	1061	-	-
Poland (PL)	-	-	4198	-	-	-	-
(Russia (RU)	-	-	242	2909	99	-	-
Sweden (SE)	811	1133	318	-	-	116	753
Atmospheric deposition	181	394	1046	150	93	105	118
Belarus (BY)	-	-	349	-	407	-	-
Czech Republic (CZ)	-	-	57	-	-	-	-
Ukraine (UA)	-	-	47	-	-	-	-
MAI	2675	2773	7360	3600	2020	1601	1687

“-” not applicable,

# see Table 1

Source: NIC, 2023

Table 4.

Total phosphorus (TP) input ceilings in tons per year for total river as well as the country contribution to each of the transboundary rivers.

River	Basin^#	NIC	Country
River	Basin^#	NIC	DE	FI	LT	LV	PL	RU	BY	CZ	UA
Nemunas	BAP	913	-	-	628	-	-	-	285	-	-
Barta	BAP	25	-	-	5	20	-	-	-	-	-
Venta	BAP	106	-	-	20	86	-	-	-	-	-
Lielupe	GUR	302	-	-	135	167	-	-	-	-	-
Daugava	GUR	941	-	-	40	395	-	99	407	-	-
Oder	BAP	1554	132	-	-	-	1365	-	-	57	-
Vistula	BAP	2350	-	-	-	-	2240	-	63	-	47
Pregolya	BAP	147	-	-	-	-	51	96	-	-	-
Neva	GUF	1399	-	20	-	-	-	1379	-	-	-

“-” not applicable,

# see Table 1

Source: NIC, 2023

Table 5.

Remaining phosphorus reduction country by basin in percentages of NIC by 2020.

Country	Baltic Sea basin^#
Country	BOB	BOS	BAP	GUF	GUR	DS	KAT
Denmark	n/a	n/a	125	n/a	n/a	-	-
Estonia	n/a	n/a	117	39	36	n/a	n/a
Finland	-	8.0		107	n/a	n/a	n/a
Germany	n/a	n/a	119	n/a	n/a	-	n/a
Latvia	n/a	n/a	66	n/a	24	n/a	n/a
Lithuania	n/a	n/a	55	n/a	-	n/a	n/a
Poland	n/a	n/a	114	n/a	n/a	n/a	n/a
Russia	n/a	n/a	151	35	26	n/a	n/a
Sweden	3.8	-	129	n/a	n/a	-	-
Belarus	n/a	n/a	148	n/a	61	n/a	n/a
Czech Republic	n/a	n/a	114	n/a	n/a	n/a	n/a
Ukraine	n/a	n/a	279	n/a	n/a	n/a	n/a

”-” no remaining reduction, n/a – not applicable,

# see Table 1

Source: NIC, 2023

Table 6.

Remaining phosphorus reduction country in tons by 2020.

Country	Baltic Sea basin^#
Country	BOB	BOS	BAP	GUF	GUR	DS	KAT
Denmark	n/a	n/a	26	n/a	n/a	-	-
Estonia	n/a	n/a	11	88	67	n/a	n/a
Finland	-	100		338	n/a	n/a	n/a
Germany	n/a	n/a	241	n/a	n/a	-	n/a
Latvia	n/a	n/a	111	n/a	255	n/a	n/a
Lithuania	n/a	n/a	388	n/a	-	n/a	n/a
Poland	n/a	n/a	4766	n/a	n/a	n/a	n/a
Russia	n/a	n/a	365	1010	25	n/a	n/a
Sweden	31	-	410	n/a	n/a	-	-
Belarus	n/a	n/a	518	n/a	248	n/a	n/a
Czech Republic	n/a	n/a	65	n/a	n/a	n/a	n/a
Ukraine	n/a	n/a	131	n/a	n/a	n/a	n/a

”-” no remaining reduction; n/a – not applicable;

# see Table 1

Source: NIC, 2023

Table 7.

Assessment of progress towards total phosphorus NIC by 2020 for Poland by Baltic Sea basins.

Total N (TN)	Baltic Sea basin^#
Total N (TN)	BOB	BOS	BAP	GUF	GUR	DS	KAT
A: Input Ceiling (NIC BSAP2021) [t]			4198
B: Estimated input 2020 [t]			8167
C: Inputs 2020 [t] incl. uncertainty (test value)			8964
Extra reduction by 2020 (A-C) [t]
Remaining reduction to fulfill NIC by 2020			4766
Remaining in % ceiling			114
Significant changes [%] since reference period to 2020			−22

# see Table 1

Source: NIC, 2023

Table 8.

NIC assessment results of Poland for total phosphorus (TP) from Table 7 (taking into account extra reduction in neighboring basins) combined with the results of the PLC-7 (HELCOM by Sveden and Tornbjerg, 2022) source apportionment assessment for the main sources indicated for Poland.

Baltic Sea basin^#	TP NIC assessment	Remain tons	Remain % 2020 input	TP input 2020 [t]	Main TP sources [%]
Baltic Sea basin^#	TP NIC assessment	Remain tons	Remain % 2020 input	TP input 2020 [t]	natural background loads	other diffuse waterborne sources	point^## sources
BOB		0	0
BOS		0	0
BAP	↓	4766	58	8167	5.0	68	27
GUF		0	0
GUR		0	0
DS		0	0
KAT		0	0

„Load 2020” is the estimated load from Table 7

# see Table 1;

## from wastewater treatment plants, industrial plants with separate discharges and aquaculture plants

Source: NIC 2023

Table 9.

Total phosphorus (TP) inputs to the Baltic Sea basins compared with detailed source apportionment. As in Table 8, but with a more detailed breakdown of sources.

Baltic Sea basin^#	Discharging into inland waters TP [%]									Discharging directly into the sea TP [%]
Baltic Sea basin^#	AGL	ATL	MFL	NBL	SCL	SWL	AQL	INL	MWL	AQL	INL	MWL
BOB
BOS
BAP	60	1.0	1.5	5.09	2.8	1.8	2.0	1.5	23	0	0.28	0.45
GUF
GUR
DS
KAT

# see Table 1

AGL – agricultural loads, ATL – atmospheric inputs on inland surface waters, MFL – managed forestry, NBL – natural background load, SCL – scattered dwelling load, SWL – storm water loads, AQL – aquaculture load, INL – industrial loads, MWL – municipal wastewater

Source: NIC 2023

Structure of phosphorus loads at sources in five regions – absolute values.
MUN–municipal point sources, IND – industrial point sources, AQU – aquaculture, ATS – atmospheric deposition, TRS – transgenic cargo, SWS – overflows and surface runoff from urbanized areas, SCS – sewage from unsewered areas, AG – agriculture, ATS – direct atmospheric deposition MFS – commercial forests and wastelands, NBS – natural background TRS – cross-border cargo
Source: National Report, 2020

The structure of river phosphorus loads in five regions – absolute values.
River loads from: MUN – municipal point sources, IND – industrial point sources, AQU – aquaculture, SWL – sewage from storm overflows of combined sewers and surface, subsurface and ground runoff from undeveloped areas (excluding loads from sanitary sewage from unsewered areas and from the natural background), SCL – sanitary sewage from non – sewered areas, ATS – atmospheric deposition, AGL – agriculture, ATL – atmospheric precipitation on the surface of inland waters, MFL forests and wastelands, NBL – natural background, TRL – transboundary sub – catchments outside Poland, UKL – unknown sources
Source: National Report, 2020

Normalized phosphorus loads at sources from Polish part of the Baltic Sea catchment area in 2000, 2006, 2012, 2018
MUN – municipal point sources, IND – industrial point sources, AQU – aquaculture, SWS – overflows and surface runoff from urbanized areas, SCS – sewage from unsewered areas, AGS – agriculture, ATS – direct atmospheric deposition, MFS – commercial forests and wastelands, NBS – natural background, TRS – transgenic cargo, UNS – loads of unknown origin, D – direct, I – indirect
Source: National Report, 2020

Normalized river loads of phosphorus from Polish part of the Baltic Sea catchment area in in 2000, 2006, 2012, 2018
River loads from: MUN – municipal point sources, IND – industrial point sources, MWL – municipal sewage treatment plants, INL – industrial sewage treatment plants, INL – industrial sewage treatment plants, FIL – aquaculture (salmon farming), SWL – sewage from storm overflows of combined sewers and surface, subsurface and ground runoff from undeveloped areas (sanitary sewage from unsewered areas and from the natural background), SCL – sanitary sewage from non-sewered areas, AGL – agriculture, ATL – atmospheric precipitation on the surface of inland waters, MFL – municipal sewage treatment plants, NBL – natural background, TRL – transgenic sub-catchments outside Poland, UNL – unknown sources, D – direct, I – indirect
Source: National Report, 2020

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DOI: https://doi.org/10.2478/cag-2025-0015 | Journal eISSN: 3071-740X (formerly 2956-9494) | Journal ISSN: 2081-2787

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Language: English

Page range: 169 - 183

Submitted on: Aug 18, 2025

Accepted on: Nov 28, 2025

Published on: Jan 31, 2026

Published by: Institute of Soil Science and Plant Cultivation

In partnership with: Paradigm Publishing Services

Publication frequency: Volume open

Keywords:

HELCOM,

Pollution Load Compilation (PLC),

Baltic Sea,

phosphorus pollution,

Nutrient Input Ceiling,

Related subjects:

© 2026 Alicja Pecio, published by Institute of Soil Science and Plant Cultivation
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 54 (2025): Issue 2 (June 2025)

The share of Poland in the phosphorus pollution status of Baltic Sea in the light of HELCOM PLC research

Figures & Tables

Figure 1.

Table 1.

Figure 2.

Figure 3.

Table 2.

Table 3.

Figure 4.

Table 4.

Table 5.

Table 6.

Table 7.

Table 8.

Table 9.

Figure 5.

Figure 6.

Figure 7.

Figure 8.

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