Racing-coast-start
Racing-round
Club-2-Porsche
Junior-Sailing-5
Racing-bmw
Racing-dinkum-v-sea-legs
Junior-Sailing-6

Milford Estuary & Tidal Sill

The Estuary

Important Notes
Keep to starboard / Speed Limit: 5 knots / Magnetic Heading 250 /070 degrees.
As a matter of courtesy, skippers going out are expected to give way to those that are coming in.
Download Entry Chart 

Approximately 6 metres wide the approach channel is marked by two starboard hand beacons. One is at the outer end and one inner half way between that and the cliff. The top of these beacons are painted green like all others on the New Zealand coast.

When street lighting is on, the channel is also marked by a constant tri colour light but the light is not particularly brilliant and the white sector can be confused with the green in the final approach.

When the wind is onshore (easterly) vessels with limited power should come in slowly so they have enough power in reserve to manoeuvre out of a wave broach. Yachtsman are well advised to set a headsail of appropriate size to the conditions and sheet amidships to keep the bow ahead and minimise risk of a broach.

Following a prolonged period of northerly winds large patches of floating seaweed can exist in the creek entrance. These have on occasion fouled propellors and you need to exercise caution.

Approximate Entry / Exit Times

Using the LINZ Tide Tables as a guide add at least 1.0 metres of depth to your draft to forecast entry and exit times into the Marina.

In a perfect world a vessel of 1.0m draft would use 2.0m predicted tidal height, a vessel of 1.5m would use 2.5m predicted tidal height and so forth. Allow some room for error – say add 0.2m –  as the tide does not always reach the predicted height. This can be the case with a powerful high pressure system over the country or if  the winds are strong from the west.

In easterly conditions, if there is a swell allow for greater depth to more than compensate for the swell troughs and waves. It may be more prudent to wait it out until conditions have subsided so you can enter.

The Marina is ideally suited as a regular berth for boats with drafts 1.5m (4′.6″) or less.

Primary Means of Navigation – The Mark 1 “Eyeball”

It is recommended you mark on your marina ladder the height the water level needs to reach and note the corresponding water level on marks oustide the marina sill e.g. the rocks 10 – 20 metres immediately northeast of the sill (see picture above), the structural work of the Milford Beacons and the Castor Bay Reef Marker at Rahopara Point.

Note: When the tide is at the level of the concrete caissons there is 1.0 meters of water there.

Walk along the marina and estuary at very low tide and study the features. Note the Marina Beacons and their structure. Pick points on the beacons, reefs, and rocks where the water level needs to be for your safe entry and exit. For example, the small domed rock adjoining the Castor Bay Reef marker – Rahopara Point (Fl G5s3m2M). Note the height of tide on this  rock as it corresponds to the required water level for safe entry and exit at your marina berth.

Technological Assistance

As a general guide and in flat water conditions if your vessel has a 1.5m draft, click on this link, select Milford as your location, use 2.65m height on the graph as the minimum tidal height for entry and exit times. This should allow you some room (0.15m) for variances in tidal height predictions. There are a number of mobile phone / tablet / ipad / navigation applications with charts and tide graphs which are extremely useful to calculate safe entry and exit times.

The Sill

Important Notes
The sill closes (door comes up) on the outgoing tide – 2h 20 mins before Low Tide.
The sill opens (door goes down) on the incoming tide – 2h 10 mins after Low Tide.

This device is unique to New Zealand and maintains an operational water level in the marina at low tide so that vessels remain afloat at low tide. Developed by Les Rees of Rees & Jones, the sill is located between two concrete caissons. Vessels should at all times cross the sill between the steel uprights. Generally when the tide is level with the top of the caissons there is 1.0 metres of water there. The top of the block on the Outer Mark is about the same as the same as the top of the caissons. The details of the operation of the tidal sill can also be found in the MCC 2016 Yearbook.

The operation, maintenance, funding and control of the sill is the responsibility of Milford Mariners Incorporated.

Got Stuck?

If you are ever caught out and appear to be getting stuck, have a reaction plan. For example, have the crew lean the boat to one side and try to move off. Think of ways to reduce your draught. Lighten the load, use the anchor to advantage. Have a tow line ready. Depending on the weather and tide, launches, powerboats are your best bet to rescue you – as opposed to other yachts who may not be able to risk grounding themselves. Don’t panic – re assure your crew. If you have to hop off your boat you should be able to standup out of the water. Wear some footwear to prevent any cuts from oysters etc. The sand is firm underfoot at the estuary corner. The rocks are not so hard, so in calm water you will probably get away with cosmetic damage. Call the Coast Guard or a fellow mariner.

On the bright side you will meet new people, provide entertainment to the beach goers, have your vessel photographed at unusual angles, incident maybe reported in the local paper, possibly a gentle ribbing or sympathy from fellow boaties – who at some stage in their lives may have escaped a similar fate here or elsewhere by a whisker themselves. The major dent will be to your pride!