The anomaly of shortly cut lawns, in rainy Hilo, on google maps! (homes, moving)

[HiloDiver]

Originally Posted by OpenD

Looking at the daily rainfall distribution on the following NWS chart, one can see that there has been measurable rainfall in Hilo 309 days out of the last 365, or 85% of all days. Whether a typical overnight light rain, or a quick torrential downpour, most days some rain is going to fall sometime, which is why everything growing is generally green and lush in the area.

I'm going to feel right at home there!

[BigIslandBum]

Originally Posted by Tiger Beer

Which begs another question...isn't the lawn always way too saturated with water, to really do anything on it?

Or is it volcanic rock just below the surface enough, that it dries fairly quickly or something?

I have pretty deep soil in the yard and it generally dries out pretty quickly. Around the avocado trees stays a bit squishy due to the trees blocking the sun - I've come close to getting my riding mower stuck a few times.

[hotzcatz]

Ah, when folks look at the rainfall map, they usually try to equate what that amount of rain would mean in the area they are used to. Frequently, when folks are moving here from the mainland and considering buying property, they want to do a "perc test" which is something to do with percolation of water through the soil which basically answers the question of how well it drains. So, adding those two things together, it is understandable as to why many folks are concerned about the amount of rain in Hilo.

We don't do perc tests in Hilo because apparently, to do a perc test, one digs a hole and dumps a bucket of water into the hole and then measures how long it takes the water to go away. In Hilo and a lot of the Puna, Volcano, Ka'u and Kona areas, the water doesn't stay around long enough to be measured. So, no perc tests and no concern about the amount of annual rainfall in Hilo.

Hilo does flood occasionally, but it takes six to eight inches of rain per hour for several hours usually on top of multiple heavy rain days in order to flood it. It also doesn't stay flooded for more than an afternoon or one day and usually most of the problem with the flooding is the rocks that got moved onto the road by the moving water.

[HiloDiver]

Originally Posted by hotzcatz

Hilo does flood occasionally, but it takes six to eight inches of rain per hour for several hours usually on top of multiple heavy rain days in order to flood it. It also doesn't stay flooded for more than an afternoon or one day and usually most of the problem with the flooding is the rocks that got moved onto the road by the moving water.

That's a relief! We have flash floods here, they are horrid, and I lost a car to flooding where I lived previously. Both places, it takes a long time to drain.

[Tiger Beer]

Originally Posted by hotzcatz

Ah, when folks look at the rainfall map, they usually try to equate what that amount of rain would mean in the area they are used to. Frequently, when folks are moving here from the mainland and considering buying property, they want to do a "perc test" which is something to do with percolation of water through the soil which basically answers the question of how well it drains. So, adding those two things together, it is understandable as to why many folks are concerned about the amount of rain in Hilo.

We don't do perc tests in Hilo because apparently, to do a perc test, one digs a hole and dumps a bucket of water into the hole and then measures how long it takes the water to go away. In Hilo and a lot of the Puna, Volcano, Ka'u and Kona areas, the water doesn't stay around long enough to be measured. So, no perc tests and no concern about the amount of annual rainfall in Hilo.

Hilo does flood occasionally, but it takes six to eight inches of rain per hour for several hours usually on top of multiple heavy rain days in order to flood it. It also doesn't stay flooded for more than an afternoon or one day and usually most of the problem with the flooding is the rocks that got moved onto the road by the moving water.

Interesting, it certainly gives me a new perspective on the Puna/Hilo side.

[mdand3boys]

Originally Posted by hotzcatz

Ah, when folks look at the rainfall map, they usually try to equate what that amount of rain would mean in the area they are used to. Frequently, when folks are moving here from the mainland and considering buying property, they want to do a "perc test" which is something to do with percolation of water through the soil which basically answers the question of how well it drains. So, adding those two things together, it is understandable as to why many folks are concerned about the amount of rain in Hilo.

We don't do perc tests in Hilo because apparently, to do a perc test, one digs a hole and dumps a bucket of water into the hole and then measures how long it takes the water to go away. In Hilo and a lot of the Puna, Volcano, Ka'u and Kona areas, the water doesn't stay around long enough to be measured. So, no perc tests and no concern about the amount of annual rainfall in Hilo.

Hilo does flood occasionally, but it takes six to eight inches of rain per hour for several hours usually on top of multiple heavy rain days in order to flood it. It also doesn't stay flooded for more than an afternoon or one day and usually most of the problem with the flooding is the rocks that got moved onto the road by the moving water.

BINGO! You nailed it!

If one looks at a map, they will notice that Hilo and South of Hilo has no rivers or streams! How can that be with that much rain?

It is the lava. There are so many holes that it just all drains away!

[Tiger Beer]

Originally Posted by mdand3boys

BINGO! You nailed it!

If one looks at a map, they will notice that Hilo and South of Hilo has no rivers or streams! How can that be with that much rain?

It is the lava. There are so many holes that it just all drains away!

Actually that's pretty interesting as well. I hadn't thought about that lack of rivers before. It also explains that seemingly thin layer of grass.

[OpenD]

Originally Posted by hotzcatz

Frequently, when folks are moving here from the mainland and considering buying property, they want to do a "perc test" which is something to do with percolation of water through the soil which basically answers the question of how well it drains.

Perc test is used in engineering a septic tank system, and in Hawai'i has to submitted along with an application for an IWS (Individual Wastewater System). Just as the Big Island has a wide range of climates... 11 of the world's 13 climate zones can be found on the BI... there are also many different soil types, each with its own drainage characteristics. Some drain fast, some don't.

Originally Posted by hotzcatz

We don't do perc tests in Hilo because apparently, to do a perc test, one digs a hole and dumps a bucket of water into the hole and then measures how long it takes the water to go away.

Basically correct, but it's a bit more involved than that. For anyone who is interested, here is the Hawai'i government's official protocol for running a perc test to be submitted with a permit application. http://hawaii.gov/wastewater/pdf/sef.pdf

Originally Posted by hotzcatz

In Hilo and a lot of the Puna, Volcano, Ka'u and Kona areas, the water doesn't stay around long enough to be measured.

Oh, that this were so in my part of Volcano, but it's actually the opposite. The perc rate in my immediate area is in the lowest category on the perc maps, and running rainwater in roadside ditches pools up in low spots throughout the community. It's not unusual for potholes in the gravel roads to take three days to drain out after the rain stops.

Originally Posted by hotzcatz

usually most of the problem with the flooding is the rocks that got moved onto the road by the moving water.

True this, and it also moves a lot of dirt and silt with it. The survey marker at the low corner of my place was buried under more than 3' of soil deposited by the rainwater draining down the slope.

[cagary]

Originally Posted by mdand3boys

BINGO! You nailed it!

If one looks at a map, they will notice that Hilo and South of Hilo has no rivers or streams! How can that be with that much rain?

It is the lava. There are so many holes that it just all drains away!

No rivers in Hilo? The rather large year round Wailuku River runs through Hilo. Doesn't it count?

[Jonah K]

Originally Posted by mdand3boys

BINGO! You nailed it!

If one looks at a map, they will notice that Hilo and South of Hilo has no rivers or streams! How can that be with that much rain?

It is the lava. There are so many holes that it just all drains away!

Someone might need to look at a better map or go fishing a little more often.

In addition to the Wailuku River that cagary mentioned, Hilo also has the Wailoa River, ʻAlenaio Stream, Honoliʻi Stream, Kaiwiki Stream, Kapehu Stream, Kapue Stream, Mokupau Stream, Nakakauila Stream, Māʻili Stream, Pāhoehoe Stream, Pakaluahine Stream, Pohakunanaka Stream, Pūkīhae Stream, Waiau Stream, Waiākea Stream and Waipāhoehoe Stream.