| Helensburgh, No 1 Reservoir | |
| Location: | Helensburgh, Scotland |
| Pushpin Map: | Scotland Argyll and Bute |
| Coords: | 56.0186°N -4.7188°W |
| Type: | Reservoir |
| Basin Countries: | Scotland, United Kingdom |
| Area: | 39500m2 |
| Volume: | 117000m2 |
| Elevation: | 107m (351feet) |
The Helensburgh No. 1 reservoir is of the non-impounding variety. It is no longer part of the local water supply system and is used by Helensburgh Angling Club. The earthen dam is 6 metres high and records show it was constructed before 1868.[1]