---
title: "Types of rain gauges with sketch"
subject: "Engineering Hydrology"
chapter: 2
key: "semester_5/engineering_hydrology:rain-gauge-types"
source: https://www.bctengineer.com/q/semester_5/engineering_hydrology/rain-gauge-types
site: BCT Engineering
---

# Types of rain gauges with sketch

Engineering Hydrology · Chapter 2: Precipitation

- Asked in: 2066 Magh (old course), 8 marks
- Video: [WRE Module1 [PART04] - Measurement of rainfall using Rain Gauges - Types of Rain Gauges](https://www.youtube.com/watch?v=dymWE_eh_Sw) — AM CIVIL ACADEMY
- Answer checked by Claude Sonnet 5.5 on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_5/engineering_hydrology/rain-gauge-types
- Whole chapter: https://www.bctengineer.com/md/semester_5/engineering_hydrology/chapter-2

## Question

Explain different types of rain gauges with neat sketch.

## Short answer

Rain gauges are non-recording (Symons’ gauge with 12.7 cm funnel, read daily) and recording (tipping-bucket, weighing, float-siphon) that give intensity. Gauges are sited on open level ground 30 cm high, away from obstructions at least twice their height.

## Answer

Rain gauges measure the depth of rainfall (mm) at a point. They are of two kinds: non-recording and recording.

### A. Non-recording (Symons') gauge
A funnel of 12.7 cm diameter sits on a cylindrical vessel and collects rain into a bottle; the depth is read by a graduated measuring jar once a day (8:45 am in Nepal).

```text
   |<-- 12.7 cm -->|
    \             /   Funnel
     \___________/
      |  bottle  |   <- collecting can
      |__________|
   ========ground=======
```

It is cheap and simple, but gives only daily totals and needs an observer.

### B. Recording gauges
1. **Tipping-bucket gauge:** Rain falls through a funnel onto a two-compartment bucket balanced on a pivot. When 0.25 or 0.5 mm of rain fills one compartment it tips, empties, and brings the other under the funnel. Each tip closes a switch and is recorded electronically. It gives the intensity but may under-record in very heavy rain.

```text
     funnel
       \ /
     [ \/ ]   two-compartment bucket
      /\  tips at fixed volume
   pivot   -> pulse to recorder
```

2. **Weighing-bucket gauge:** The collecting bucket sits on a spring balance; the increasing weight moves a pen over a clock-driven drum chart, giving a continuous mass curve. It records snow and hail also.

3. **Float-type (natural siphon) gauge:** A float in a chamber rises with the rain collected, moving a pen on a rotating drum. When the chamber is full, a siphon empties it automatically and the pen returns to zero. It gives a continuous mass curve (Dines or Hellman type).

### Comparison
| Type | Output | Gives intensity? |
|---|---|---|
| Symons' | Daily depth | No |
| Tipping bucket | Pulses per tip | Yes |
| Weighing | Continuous chart | Yes |
| Float/siphon | Continuous chart | Yes |

#### Siting
The gauge is placed on open level ground, with its funnel rim horizontal 30 cm above the ground, away from obstructions at a distance of at least twice their height.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What does a Symons' gauge give?
   A. Continuous intensity
   B. Pulses per tip
   C. Daily total read once a day
   D. Weight chart
   Answer: C. Non-recording, read at 8:45 am; no intensity. (Key point: Symons' gauge)

2. How does a tipping bucket record?
   A. Spring balance moves a pen
   B. Float with siphon
   C. Manual measuring jar
   D. Bucket tips at fixed volume, each tip closes a switch
   Answer: D. Tips of 0.25 or 0.5 mm are recorded electronically. (Key point: Tipping bucket)

3. What does the siphon in a float-type gauge do?
   A. Empties the chamber automatically so pen returns to zero
   B. Measures weight
   C. Tips the bucket
   D. Closes switch
   Answer: A. When full, siphon empties it. (Key point: Float gauge siphon)

4. Which siting rule is correct?
   A. Under trees
   B. Open level ground, rim 30 cm above ground, distance at least twice obstruction height
   C. On a roof
   D. 1 m from a wall
   Answer: B. Avoid exposure errors. (Key point: Siting)

## Related in Engineering Hydrology

- [Number of additional rain gauges required](https://www.bctengineer.com/question.md?key=semester_5%2Fengineering_hydrology%3Aoptimum-raingauges-7stn) — Engineering Hydrology, chapter 2
- [Optimum number of rain gauges](https://www.bctengineer.com/question.md?key=semester_5%2Fengineering_hydrology%3Aoptimum-raingauge-number) — Engineering Hydrology, chapter 2
- [Optimum rain gauges for 10% error, six stations](https://www.bctengineer.com/question.md?key=semester_5%2Fengineering_hydrology%3Aoptimum-raingauges-6stn-240) — Engineering Hydrology, chapter 2
- [Additional rain gauges for 5% error, seven stations](https://www.bctengineer.com/question.md?key=semester_5%2Fengineering_hydrology%3Aoptimum-raingauges-7stn-130) — Engineering Hydrology, chapter 2, asked 2×
- [Thiessen average rainfall, four gauges at rectangle corners](https://www.bctengineer.com/question.md?key=semester_5%2Fengineering_hydrology%3Athiessen-rectangle-four-gauges) — Engineering Hydrology, chapter 2