Research and analysis

Lincolnshire and Northamptonshire water situation: June 2025 summary

Updated 15 July 2025

Applies to England

• Publication for Northern Ireland
• Publication for Scotland
• Publication for Wales

1. Summary

Overall, June was another very dry month, continuing the recent pattern of below average rainfall. Precipitation ranged from 35% to 48% of the long term average (LTA), classifying conditions as below normal for the time of year. As a result of this and the preceding dry months, both the 3-month and 6-month rainfall maps in the main report display notably to exceptionally low totals. Most notably, April to June 2025 was the second driest on record for the Witham to Chapel Hill hydrological area.

The persistent dry and hot weather led to high soil moisture deficits (SMD) throughout June, which ended the month at exceptionally high levels across all hydrological areas. River flows continued to decline, although most flow classifications remained unchanged from the previous month. Groundwater levels also declined, with most classifications staying the same; the main exception was at Dunholme Road, where levels dropped from normal to exceptionally low during June. Most reservoir levels are currently below target for the time of year, but none are alarmingly low at present. The Trent-Witham-Ancholme transfer scheme operated throughout June, and the Slea Augmentation scheme was switched on around mid-June.

2. Rainfall

Like the recent months preceding it, June was a relatively dry month with rainfall varying between 35% to 48% of the LTA. As a result, rainfall was classified as below normal for the time of year across all 6 hydrological areas. Most of the limited rainfall occurred during the first week of the month. An east-west split is evident, with western catchments receiving less rainfall than those in the east. April to June 2025 was the:

• second driest on record for the Witham to Chapel Hill hydrological area
• third driest for the Upper Welland and Nene
• fourth driest for the Grimsby Ancholme Louth hydrological area

For the region as a whole, it was the fourth driest April to June period on record (since 1871). The 6-month rainfall map in the full report reflects a similar pattern, showing notably to exceptionally low levels with the same east-west contrast. For the area as a whole, January to June 2025 ranks as the seventh driest on record, with individual hydrological areas ranking between the sixth and fifteenth driest for that period. While the 12-month trend still shows mostly normal rainfall totals due to the impacts of a wet winter, below normal to notably low levels are now appearing in the northern parts of the area.

3. Soil moisture deficit and recharge

Another hot and dry month saw SMD built up further across all 6 hydrological areas. The wet end to May and somewhat wet start to June briefly saw SMD decrease to above normal to notably high levels for the time of year. However, once that rain stopped (and the temperatures increased) SMD soon rose back up to exceptionally high levels for the time of year which is where they ended the month of June. For the Lincolnshire and Northamptonshire (LNA) area, the average SMD by the end of June was 130mm, a significant increase from 108mm at the end of May.

4. River flows

River flows varied between 13% to 87% of their LTA, classifying flows as exceptionally low to normal for the time of year. The normal flows are mostly observed in the south-west of the area. Most flow classification are unchanged, with the exception of Wansford on the Nene (moving from below normal to notably low) and Kates Bridge plus King Street on the Glen (moving from normal to below normal). Langworth on the Barlings Eau remains the only site recording exceptionally low levels for the time of year.

5. Groundwater levels

Groundwater levels ranged from normal to exceptionally low for the time of year, with most sites remaining unchanged from the previous month. The most notable change occurred in the Lincolnshire Limestone at Dunholme Road, where levels dropped from normal at the end of May to exceptionally low by the end of June. Similarly, Grange de Lings, also on the Lincolnshire Limestone, reported exceptionally low levels for June. Grange Farm, another Lincolnshire Limestone site, declined from normal to below normal levels during the month. For the chalk aquifers we report on, classifications remained the same as in May, although a general seasonal decline was observed, resulting in levels now ranging from the lower end of normal to below normal.

6. Reservoir stocks

Due to a warm and dry June, reservoir stocks continued to decline across the region. All reservoirs are now below their target levels, except for Pitsford, which remains just at target. Although below target, no reservoir levels are currently at alarmingly low levels.

7. Environmental impact

The Trent-Witham-Ancholme transfer scheme has been in operation throughout June, pumping water both from the Trent into the Witham and from the Witham into the Ancholme. The Slea augmentation scheme commenced pumping on the 20 June and has been pumping continuously since then. The Gwash-Glen Transfer scheme remains off. During June there were 27 hands-off-flows and hands-off-levels active across the area. There were no flood alerts or warnings issued.

8. Forward look

8.1 Probabilistic ensemble projections for river flows at key sites

August 2025: North Brook and Wansford are both showing an increased probability of lower than normal flows. Nene Northampton is showing a slightly increased probability of normal flows.

December 2025: All sites are showing an increased probability of below normal flows.

8.2 Probabilistic ensemble projections for groundwater levels in key aquifers

September 2025: Hanthorpe and Barton are showing an increased probability of below normal levels. Grainsby is showing an increased probability of normal levels.

March 2026: All sites are showing a greatly increased probability of lower than normal levels.

Author: Pan Hydrology Team, Hydrology-EAN-and-LNA@environment-agency.gov.uk

All data are provisional and may be subject to revision. The views expressed in this document are not necessarily those of the Environment Agency. Its officers, servants or agents accept no liability for any loss or damage arising from the interpretation or use of the information, or reliance upon views contained in this report

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