In addition to the LoRaWAN adoption, partsof the city’s measuring systems have been modernizedto integrate the individual reservoirsand plants into a cloud-based monitoring system.This provides the city’s water masters withall information they need at any time, whetherthey are using a mobile device or at their computerin the operations center. The LoRaWANspecification is a networking protocol designedto wirelessly connect battery operated devicesto the internet in regional, national, or globalnetworks, and targets key Internet of Things(IoT) requirements such as bi-directional communication,end-to-end security, mobility, andlocalization services. That has changed with Oberzent’sadoption of a new low-power LoRaWANnetwork (long range wide area network) forits water management system. In these cases, a cable can be strung across the river, from which a hydrologist can move across and sample and measure the river as needed.Acritical task for a water master in Oberzent,the third largest city in terms ofarea in the German state of Hessen,is to visit each water reservoir and plant individuallyto read the measured values and checkthe instruments. USGS hydrologists can't always count on a nice, wide bridge being available for hydrologists to sample from, and sometimes it is too dangerous (due to high flows or floating debris) to use a boat for sampling.

The hydrologist has to move the sampler up and down at a steady rate until the bottle is filled, while at the same time being sure not to smash the nozzle into the mud on the stream bed! Sometimes only a cableway will do

The heavy metal 'fish' which holds the sampling bottle is needed to keep the sampler from being pushed downstream, as it is important to representatively sample the vertical column of water at each sampling point across the river.

If the water is moving fast or if the depth is too deep, then a crane with an electric motor (or hand crank for especially hardy hydrologists) is used to obtain the water sample (above picture). Bridges make this task very convenient, although samples can be taken using a boat, if no bridge is available. So, to understand the water properties of the whole river it is necessary to obtain individual samples at set increments across the river. It takes longer for all the water in large rivers to mix together. Sediment work using samplers, laser diffraction, and acoustics on the Kickapoo Creek near Bloomington, Illinois, on April 22, 2011. There may be a tributary coming in from the left side above the sampling point or there may a wastewater treatment outflow pipe a mile upstream on the right bank. In larger rivers, there is more chance of variability in the water characteristics and quality across the river. It takes a lot more work to get a water sample from a larger river, as this picture shows. She can sample different horizontal sections separately by using a different bottle for each vertical section or use a single bottle for the whole stream. The bottle has a small tube in it that allows only a small amount of flow into the bottle, and thus, the hydrologist can regulate how much water is sampled at various points in the stream. There is a bottle inside the white container at the end of the pole (bottom picture). That entails taking small amounts of water from numerous horizontal sections across the stream, at regular intervals, as the middle picture shows. Quite often it is important to take a water sample that represents the stream as a whole. Note how the sampler always stands downstream from the sampling point-don't want to stir up any sediment that could alter the chemical analysis of the water sample. Sampling a small streamįor a small stream where the water is well mixed, it is sometimes possible to take a single 'grab sample', where the hydrologist just dips a bottle in the stream at one location, still trying to move the bottle up and down to sample the entire vertical column of water. Sampling methodology also depends on the type of water sample needed. As the left-side pictures below show, often a hydrologist can simply step out into a small stream and dip a bottle in at the appropriate place, but on larger rivers, it might be necessary to build a cableway and take water samples from high above the water surface. Also, I should add, on the ability of the water scientist to be able to access the water. The USGS has to utilize different methods and equipment when taking a sample of water from a stream-it all depends on the size of the stream, how deep the water is, and how fast the water is moving. USGS scientists collect water samples for chemical analysis from an excavated pond in the New Jersey Pinelands.

Integrated age of water