Hydroacoustic Doppler Technology: A Key Element in the Improvement of Winter Hydrometric Data Quality

Figures & data

Figure 1. Illustration of the miscalculation of area from open flow stage-area ratings during winter.

Figure 2. Location of the Ville Mercier hydrometric station.

Figure 3. Evolution of the under-ice Index Velocity Relationship (IVR) between 2005 and 2009.

Table 1. Comparison of measured discharge and computed streamflow.

	Qmeas	SDR (non-corrected)		IVR 2009
		Q	Error	Q	Error
Date of Measurement	m^3/s	m^3/s	%	m^3/s	%
2004-01-21	17.27	31.44	82.0	18.16	5.1
2004-03-02	13.95	26.10	87.1	12.53	10.2
2005-02-03	10.94	17.44	59.5	10.92	0.2
2005-03-08	11.39	15.02	31.9	11.68	2.5
2006-01-31	41.86	46.07	10.1	39.27	6.2
2006-03-09	16.58	17.99	8.5	15.54	6.3
2008-02-04	26.30	32.68	24.3	28.43	8.1
2008-02-25	24.35	28.99	19.1	26.70	9.7
2009-01-19	15.85	28.96	82.7	15.70	1.0
2009-03-02	60.07	63.8	6.2	59.40	1.1
Mean Absolute Error (%)			41.1		5.0

Figure 4. Comparison of computed streamflow (IVR, non-corrected SDR, corrected SDR) for Winter 2009.