Plainwater Home Page
07 Aug 2017: Added HEC-14 Riprap Apron calculator.
28 July 2017: Added HEC-22 spread check calculator.
20 July 2017: Added HEC-15 riprap lining calculator.
08 July 2017: Added the very comprehensive Civil Engineering Resource Guide, by SmartScholar.
07 July 2017: Added the Grass Lining Manning’s n and Lining Stability calculators, based on Chapter 4 of HEC-15 Design of Roadside Channels with Flexible Linings, under Calculators. Also added the entire HEC-15 Chapter 4 Vegetative Lining and Bare Soil Design, under Water.
08 May 2015: Added the Culvert Inlet Control Calculator – to compute culvert headwater depth for inlet control conditions, using the HY-8 polynomial equations referred to in HDS-5 Hydraulic Design of Highway Culverts, Third Edition.