OK it is March 2007 & we have water issues around Darwin, Adelaide River township, Jabiru & Oenpelli due to the Tropical Low Pressure bringing in a lot of moisture. Some places up that way had 200+ mm in 24hrs. (290+mm on the Daly River)

The Katherine River had a nice dump way up at its source on the 1st & 2nd March 2007 with 138 mm & 69mm the day before at the upper reaches & not really much much elsewhere (do 40-70mm overnight falls really count up here?)

There is a disturbing figure at the Central Arnhem Plateau of 79mm & 235 mm, however if my theories are correct this weather station is pivotal on the plateau (meaning the rainfall will spread to Katherine River & South Alligator Rivers, so this recording must be taken with a grain of salt, although will play a part in the Katherine River flow)

Lets look at some stats when the Katherine River inundated many homes and crept into the CBD in April 2006 (a write up of this event is written here)

Comparison to April 2006 & March 2007 will cause alarm when we move to the actual "river levels" at various points along the Katherine River. BUT the current situation is VERY different, although will cause concern & the main gateway we need to keep in mind is the NITMILUK CENTRE RECORDINGS as this is the last point before Katherine Township. It must be stressed that no two events will be the same & we have seen this in previous comparisons. ie what is recorded at Nitmiluk one year may not correspond to the height in Katherine at another time due to different rates of flow & other local factors.

2006 Rainfall Stats

2007 Rainfall Stats

Rainfall of significance in Region on 04Apr06 that contributed to The Katherine Flood of 2006

195.4 MOUNT FELIX
161.0 MARY RIVER RANGERS
141.6 YEURALBA RIDGE
136.6 UPPER WATERHOUSE
136.2 EVA VALLEY
133.6 UPPER FERGUSSON
102.8 CENTRAL WATERHOUSE
95.8 UPPER 17 MILE CREEK
92.6 TINDAL RAAF
84.8 WATERHOUSE
76.4 CENTRAL ARNHEM
71.4 EDITH FARMS ROAD
64.2 TANDANGLE HILL
64.2 KATH RURAL COLLEGE
51.0 KATHERINE MUSEUM

Rainfall 05April06
(Not really Katherine River Catchment)

131.0 MATARANKA HOMESTEAD
98.0 CENTRAL WATERHOUSE
80.6 TANDANGLE HILL
64.0 WATERHOUSE
63.8 PIRLANGIMPI
63.8 LEANYER
53.0 MATARANKA STATION
50.8 KATHERINE MUSEUM

Station Name	24 hours to 9am - last 7 days 2007
Station Name	24	25	26	27	28 Feb07	01 Mar07	02 mar07
Katherine River
Central Arnhem Plateau AWS* Remember this one is claimed by the South Alligator River also	1.4	38	25	12	61	79	235
Katherine River Upper Reaches*	3.5	34	18	34	32	69	138
Sleisbeck*	1.0		1.5	13	23	26	51
Snowdrop Creek*	4.0	1.8	3.0	28	49	45	71
Birdie Creek*			1.0	19	16	22	32
West Waterhouse*	0.0	0.2	3.8	10	8.6	18	28
Fanny Creek*	0.0	0.6	0.0	9.2	17	14	23
Upper 17 Mile Creek*	3.6	0.0	8.2	4.0	8.2	3.0	9.6
Mount Felix*	2.2	4.4	2.4	1.8	30	12	15
17 Mile Creek*			3.5	0.5	17	1.5	2.5
Yeuralba Ridge*	7.0	0.0	2.8	2.0	16	11	15
Eva Valley*	1.0	0.0	13	1.6	13	18	25
Nitmiluk Ridge*	0.0	0.0	5.0	0.2	15	1.2	3.0
Nitmiluk Rangers			6.2	0.2	14		2.2
Katherine Rural College			7.2	0.8		1.0	19
Katherine Aviation Museum	0.0	0.0	1.8	1.2	8.0	0.8	15
Katherine Bridge*	0.0	0.0	0.5	0.5	8.5	0.5	16
Tindal RAAF AWS*	1.4	0.0	9.6	0.4	6.0	1.0	10.0

Rainfall figures are all very well & good, however it is the River Levels that people now watch after the rain has fallen.

I have chosen Birdie Creek as it is the final gateway before entering the Nitmiluk Gorge system (which restricts flow) before the recordings at the Nitmiluk Centre. (See this page for a Satellite visual on the mentioned sites , Birdie Creek, Nitmiluk Centre & Katherine Bridge)

The Chart below is of water height over 10 years at the Birdie Creek recording station
located on Katherine River 90km above Katherine

This image has been updated manually by me (so may be grossly incorrect)
I think I have the 8.74 metre record worked out from the NT Water Resources site, but who knows.

The chart below is the last 7 days water levels at the Birdie Creek recording station to 04March07

Katherine R near Birdie Creek* 5.45pm Sat 6.59 rising minor 03March 07 (official printout) but got a tad higher (6.7ish)a few hours later.

So Already in 2007 the Birdie Creek water levels are exceeding the 2006 Birdie Creek levels**.
**Now the charts may be out or I may be reading them incorrectly with reference to the max height recorded & the chart itself.
But take note that in 2006 we had much localised rainfall with 95mm pouring off of 17Mile Falls / Creek & feeding the Katherine River as well as local rainfall of 50mm backing up the Katherine River.

In March 2007 there is nothing significant pouring into the Katherine River (below the Gorge) that will back it up.
In fact the River should be able to spread up the creeks with ease.

The Following are the unchecked Telemetered River level recordings for Nitmiluk & Katherine Bridge.
Please note that these levels rarely match the recorded levels on the BOM river levels site. An example is the BOM recording of 4.77metres at Nitmiluk at 5AM 05March07, where it is not even close in the following charts.
(must have a different timing)
These were the recordings during 3-7 March 2007

27ish hours after the peak at Birdie Creek the lump of water reaches the Nitmiluk Centre

You san see in red the peak at Nitmiluk of 4.76 metres early Monday Morning at between 1-3AM.
In this scenario the Katherine River peaked (13.13metres) at the Katherine Bridge about 14-16 hours later between 4-7PM

The Watch is called when the River at Nitmiluk is at 3 metres. In Town at the time of the "watch" the River was on 8.45metres.
When the Category 1 warning was called (Nitmiluk @ 4.5M), the River level in town was 10.61metres.

The fastest rate of rise of the river in Katherine Township was just over 4 metres in a 24 hour period (2.25 metres in 12 hours)

The thing that annoyed me is the "official" statements that the "river may rise to 15+ metres within the next 12 hours (which was over double the current rate at the time) (and rate of rise at Nitmiluk was slowing). Katherine Bridge was on 10.61m at the time

"The Katherine Regional Counter Disaster Committee met this evening to assess conditions and at this stage the river could possibly reach 15.5 metres at the Railway Bridge within 12 hours."

More care should be taken next time and a review of the written content of the stages. (maybe it should be mentioned as 24 hours instead of 12 hours which is more realistic) (in this case)

Please note that these recordings will only relate to this volume of water and rainfall conditions for the region. Every situation will be different with different parameters in the future. (however hopefully the above may relate to a future river rise to 13metres)

As of 8.10 PM on Saturday Night 03March07 the official readings at
Nitmiluk are 1.84 & Katherine Bridge are 7.51metres
(in the last 12 hrs the river has risen 1.1metres in Katherine)

Sunday Morning now 04March07, and Katherine Bridge at 8.31M (rising at approx 8cm per hour)
All going normal as it does.
We will see the rate of rise per hour increase slightly over the coming days

2.00PM Sunday Arvo 04March07
Current level at Katherine Bridge is 9.43m (Rate of rise over last 3 hours is 50 cm)(20cm for last hour)
At Nitmiluk the level is 3.95m (15cm for last hour)

A Flood watch has been issued as the Nitmiluk Gauge hits 3Metres and risen an extra metre over the last 2 hours.
This is from the surge of water coming down from rainfall upstream of the Gorge over the last day+.
Nothing unusual about that for this time of year.
The interesting thing is the correlation of stats between this lot of river heights (with localised rainfall, ie 100+mm in Katherine itself)
And earlier this month the rainfall was very much above the Gorge & not in town (so flowed freely through the Gorge & not hindered downstream) .
The Katherine Bridge level is several metres higher at this time (in comparison to recorded levels at Gorge last time) due to local rain.
The local rainfall is already heading downstream, and we have a 12+ hr wait for the Nitmiluk water (plus 17Mile Creek/falls)
& no doubt Maud Creek, and locally tomorrow with Tindal Creek as it affects the town drain.
I don't think anything overly interesting is going to happen as nowhere near the volume is coming from Birdie Creek peak (as of yesterday's data),
but add to that tonights water & it just goes to show the parameters involved and reasoning behind the stages of flood warning categories.

Please be advised that these are just my observations and may be grossly flawed.
Do not rely on this for future reference.

1998 Birdie Creek showing 6.3m on chart (8.74 recorded in history on gauge?)	2007 Birdie Creek 5.32m @7AM 03March07
2006 Birdie Creek 5.6m + 17mile falls 100mm + localised falls in Katherine	2007 Birdie Creek 6.59 @ 6PM 06March07