Calculation of source-oriented nitrogen deposition to the Baltic Sea and revision of nutrient reduction targets as identified in the HELCOM Baltic Sea Action Plan
Background
In 2007 HELCOM Contracting Parties adopted the HELCOM Baltic Sea Action Plan (BSAP). In the eutrophication segment of the BSAP, the HELCOM Contracting Parties agreed, in order to diminish nutrient inputs to the Baltic Sea to the maximum allowable level, to take actions not later than 2016 to reduce the nutrient load from waterborne and airborne inputs aiming at reaching good ecological and environmental status by 2021. The Contracting Parties acknowledged that current environmental and nutrient reduction targets are provisional and that all the figures related to targets and maximum allowable nutrient inputs should be periodically reviewed and revised based on updated information and starting in year 2008 taking into account the results of the Fifth Pollution Load Compilation (PLC-5) and national river basin management plans.
Acknowledging that a quarter of the total nitrogen input to the Baltic Sea is airborne (of which sources outside the Baltic Sea catchment area contribute about 40% of the direct nitrogen deposition), the HELCOM Contracting Parties decided that air emissions and atmospheric deposition of nitrogen to the Baltic Sea should be included into targets and maximum allowable nutrient inputs figures.
Aim
The main aim of this activity is to revise the eutrophication related targets and maximum allowable nutrient inputs by using updated waterborne load data (PLC-5) and atmospheric deposition data which was previously not included in model calculations.
Tasks
1. EMEP to calculate:
source apportionment of nitrogen deposition originating from different sectors for one year in each of the seven-year periods (1997-2003 and 2000-2006)
nitrogen deposition to the different sub-basins originating from each country and maritime transport for the periods 1997-2003 and 2000-2006
This approach would give information on the sectoral source-apportionment for two years and allow updating of country-wise nutrient reduction requirements of the BSAP to include airborne nitrogen deposition.
2. HELCOM Fifth Pollution Load Compilation (PLC-5) data consultant and project manager to compile latest data on waterborne pollution loads to the Baltic Sea.
3. Baltic Nest Institute to recalculate nutrient reduction allocations based on latest waterborne pollution loads and the inclusion of atmospheric deposition data.
Expected outcome
1. Updated figures for the country-wise nutrient reduction requirements needed to fulfil the eutrophication related objectives of the HELCOM BSAP.
2. Improved knowledge of the sources of airborne nitrogen loads to the Baltic Sea.
Tentative timeframe for revision of figures:
| Time | Activity |
| 7-8 April 2008 | Outcomes of the Informal Meeting of PLC-5 / BNI / EMEP were presented at the BSAP IG 1/2008 to stress the need of PLC-5 data in general, more detailed data on WWTPs as well as data on agricultural loads to be provided by countries in order to start the revision of national nutrient loads allocations / reductions |
| 15 April 2008 | EMEP provided HELCOM Secretariat with detailed proposal on additional data for: |
| 15 April -15 May 2008 | HELCOM MONAS considered EMEP’s proposal by correspondence and prepared the decision for approval by HELCOM HOD 26/2008 |
| 4-5 June 2008 | A request to EMEP for additional data regarding direct deposition of nitrogen to the Baltic Sea was endorsed by HOD 26/2008 |
| 20 June 2008 | Ultimate deadline for submission of national datasets under PLC-5 periodic and annual reporting round as well as for additional data on municipal waste-water treatment plants |
| 15 Oct. 2008 | Preliminary assessment of waterborne nutrient inputs by SYKE together with additional data on airborne nitrogen deposition for 1997-2003 and 2000-2006 by EMEP should be submitted to the Secretariat and the Baltic Nest Institute (BNI) for revision of the nutrient reduction figures |
| October 2008 | Informal Working Group of PLC-5 / BNI / EMEP and HELCOM Secretariat will meet to discuss draft proposals for revision of country allocations of updated nutrient loads and reduction targets |
| 03 Nov. 2008 | Draft proposals for revision of country allocations of updated nutrient loads and reduction targets to be discussed by MONAS 11/2008 for further adoption by HOD 27/2008 or BSAP IG |
| 02 Dec. 2008 | Proposals for revision of country allocations of updated nutrient loads and reduction targets with comments by MONAS should be submitted to BSAP IG 4/2008 |
Contacts
Mikhail Durkin
Professional Secretary
HELCOM Secretariat
Tel: +358 46 850 9195
E-mail: mikhail.durkin@helcom.fi
Maria Laamanen
Professional Secretary
HELCOM Secretariat
Tel: +358 46 850 9198
E-mail: maria.laamanen@helcom.fi