Thoughts - Rapa Iti's Hydrographic Layer

Rapa Iti Island - Ikonos Image (1-55,000)

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Rapa Iti Island - Other Precision Map (Ikonos Image) Hydrography Layer (1-55,000)

I believe Rapa Iti's hydrographic layer is almost complete. I always QC my digitizing before I determine a layer finished. I am watching the Pacific Life Holiday Bowl (score Okla St 31 and Oregon 42) and composing this post. A few moment ago my mother-in-law asked what my map showed. I explained that I had mapped all of the places where water would flow during a rain storm. She thought that was interesting, but liked the colors best.

The QC of this layer will involve a final classification of the streams. They will be classified as permanent streams identified by vegetation, stream width and visible water. Any or all of these characteristics evident will cause me to classify the stream as permanent. All other streams will be classified as intermittent streams.

This system of classification will have to do short of me visiting the island for a month during the rainy season and spending the time hiking to various points about the island to study water flow. Oh well, one can dream.

Enjoy! And Happy New Year!

Thoughts - Digitizing Rapa Island's Hydrography Layer

Rapa Island, North Shore - Ikonos Image with Digitized Hydrography Layer (1:1,250)

Rapa Island, North Shore - Other Precision (Ikonos) Map with Digitized Hydrography Layer (1:1,250)

Sure, I've been busy with family, friends and 12 dozen tamales served all day Christmas day at my home. Come Christmas evening I was still entertaining guests and wishing I could continue working on my current mapping project, Rapa Island. I have mapped this island a number of times, each time not completely satisfied with the finished project. So I've decided to work on this island one more time. First I redigitized the shoreline working at scales between 1:1,250 to 1:850 using a hi-res Ikonos image. After completing the shoreline, I decided to work on the island's hydrographic layer. Initially I've classified each valley as a potential stream course. The island has a number of permanent streams fed by frequent rain storms and springs. Most of the streams I've currently mapped will be reclassified as intermittent.

Rapa Island - Other Precision (Ikonos) Map with Hydrography Layer (1:52,500)

I've mapped most of the hydrographic layer over the last 5-days, actually over the last 5-evenings. The hydrography of the western portion of the island remains to be digitized. I hope to have the layer completed within the next few days. When it is finished, I intend to digitize the vegetation layer next. I'll keep you informed as to my progress.

Enjoy! Merry Christmas and Happy New Year!