KDP categories · Top KDP authors
Hydrology (Civil, Kindle eBooks): Amazon KDP category data
Amazon Kindle eBooks Best Sellers data for Hydrology (Civil, Kindle eBooks), updated Nov 2, 2026: median price $9.99, median 2 reviews, average rating 4.4 and a KDPTop opportunity score of 22/100 (highly competitive).
| Price range (middle 50%) | $6.98 – $17.69 |
|---|---|
| Average rating | 4.4 |
| New releases (90 days) | 13% |
| Books on the list | 100 |
| Store | Kindle eBooks |
What stands out
- Its median reviews are 2% of the parent category Civil (92), one of the easier corners under it.
- Its review barrier is lower than in 95% of Kindle eBooks categories: the median best seller has only 2 reviews, so new books can chart with few.
- Prices spread wide: the middle half runs from $6.98 to $17.69, so budget editions and premium or boxed sets sell side by side.
Top 10 Hydrology best sellers
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Water Projects: The Complete DIY Guide to Building Self-Sufficient Water Systems for Your Home, Cabin, or Garden
by Evan Whitlock
- List rank#1
- Price$9.99
- Rating4.4
- Reviews23
-
The Prepper’s Survival Collection: A Beginner's Guide to Find, Filter and Purify Water + How to Grow, Preserve and Store Food for Emergency Preparedness ... Times (Self Reliance Essentials Book 3)
- List rank#2
- Price$4.99
- Rating4.8
- Reviews55
-
PREPPER’S WATER SURVIVAL BIBLE: Save Your Life with the Only Water Survival Book You’ll Ever Need! Complete Action Plan to Find, Harvest, Filter, Purify, ... Emergency! (PREPPER SURVIVAL BIBLE BOOK 1)
by CONDITION 1: READY
- List rank#3
- Price$9.99
- Rating4.7
- Reviews54
-
THE WATER PROJECTS FIELD MANUAL: A Practical, Illustrated Guide to Rainwater Harvesting, Storage, Pumps and Filtration: Step-by-Step Systems for Your Home, Cabin, or Homestead in Any Climate
by Thomas K. Langford
- List rank#4
- Price$2.99
- Rating4.8
- Reviews5
-
The Air-to-Water Handbook: An Illustrated Beginner's Guide to Building, Testing, and Safely Using Atmospheric Water Harvesting Systems
by Charles Briggs
- List rank#5
- Price$9.94
- Rating1.0
- Reviews1
-
Prepper's Water Survival Secrets: Cost-Effective Water Collection, Filtration, Purification & Storage Strategies for Your Family to Thrive in Any Crisis
by Hadassah Lewis
- List rank#6
- Price$9.99
- Rating4.8
- Reviews116
-
Into The Absolute Darkness: The Epic Drama of the First Underwater Exploration of Blanchard Springs Caverns. A True Story.
by Glenn Thompson
- List rank#7
- Price$9.99
- Rating4.9
- Reviews11
-
PREPPER’S WATER BIBLE: Proven Lifesaving Plan to Harvest, Filter, Purify And Store Water When It Becomes More Valuable Than Gold! (PREPPER SURVIVAL BIBLE BOOK Book 2)
by CONDITION 1: READY
- List rank#8
- Price$4.97
- Rating4.3
- Reviews23
-
Rainwater Harvesting Made Easy: A Beginner's Guide to Build and Maintain Your Own Sustainable Clean Water System for Your Urban Home, Rural Farm, or Homestead
by Perennial Publishing
- List rank#9
- Price$3.99
- Rating4.4
- Reviews236
-
Engineer Manual EM 1110-2-1908 Engineering and Design: Instrumentation of Embankment Dams and Levees November 2020
by United States Government US Army
- List rank#10
- Price$9.99
- Reviews-
FAQ
Is Hydrology a good niche for Amazon KDP?
Its KDPTop opportunity score is 22/100, which makes it highly competitive. The median best seller has 2 reviews and sells for $9.99.
How many reviews do you need to rank in Hydrology?
The median best seller has 2 reviews, and 89% of them have fewer than 100.
What do Hydrology best sellers cost?
The median price is $9.99; half of the best sellers are priced between $6.98 and $17.69.
Can new books break into Hydrology?
13% of the current best sellers were released in the last 90 days.
About this data
Data comes from KDPTop's daily crawl of Amazon's public Best Sellers pages; medians use the latest list. The opportunity score (0–100, higher is easier to enter) combines the review barrier, the share of low-review books, list turnover, new-release share and price.