Kekeruhan dapat diartikan sebagai ukuran relatif kejernihan air. Kekeruhan merupakan suatu kondisi air yang di dalamnya terdapat sedidkit atau banyak partikel-partikel halus yang kadang tak kasat mata sehingga diperlukan suatu alat dengan efek cahaya untuk mengukur kondisi air baku dengan skala NTU (Nephelometric Turbidity Unit). Internet of things merupakan suatu objek yang mampu melakukan suatu pengiriman data melalui jaringan internet Disini peneliti akan membuat sebuah sistem pemantauan air berbasis internet of things melalui smartphone. Berdasarkan hasil peneletian didapatkan nilai dari pengujian sensor turbidity yang dibandingkan dengan alat ukur Milwaukee Mi415 didapatkan error 0,163%. Pada perhitungan akurasi didapat nilai 99,12%. Pada data yang bervariasin dilakukan percobaan dari kekeruhan sangat rendah 1,92 NTU sampai dengan kekeruhan yang sangat tinggi 299 NTU. Pada pengujian sistem didapat notifikasi aktif ketika nilai kekeruhan diatas 5 NTU dan buzzer akan berbunyi. Dari pemantauan yang dilakukan selama 24 jam didapat dan sensor turbidity dibandingkan dengan alat ukur milwaukee didapat nilai error 0,236% dan akurasi 99,23%.

Turbidity can be interpreted as a measure of the relative clarity of water. Turbidity is a condition of water in which there are few or many fine particles that are sometimes invisible, so a tool with light effects is needed to measure the condition of raw water with the NTU (Nephelometric Turbidity Unit) scale. Here the researcher will create an internet of things-based water monitoring system through a smartphone. Based on the results of the research, the value of the turbidity sensor test which was compared with the Milwaukee Mi415 measuring instrument obtained an error of 0.163%. In the calculation of accuracy obtained a value of 99.12%. On various data, experiments were conducted from very low turbidity 1.92 NTU to very high turbidity 299 NTU. In system testing, an active notification is obtained when the turbidity value is above 5 NTU and the buzzer will sound. From the monitoring that was carried out for 24 hours, it was obtained and the turbidity sensor compared to the Milwaukee measuring instrument obtained an error value of 0.236% and an accuracy of 99.23%.