Board Members

Timothy L. Hildenbrand, President 830-709-3879 Gina Mangold 830-709-3879
Caroline A. Nentwich, Vice President 830-709-3879 Hector De La Fuente 830-709-3879
Richard A. Sultenfuss, 2nd Vice President 830-709-3879 Roy Tschirhart, Jr. 830-709-3879
JoNell M. Tarvin, Secretary/Treasurer 830-709-3879


Present Term August 2016-August 2019
Mr. Hildenbrand was appointed to fill an unexpired term on the Board of Directors in April 1999.  He was re-elected to the board in August 1999, August 2002,  2005,  2007, 2010, 2013  and again in 2016.   He held the office of  2nd Vice-President from 1999 to 2000.  In August 2000 he was elected Vice President.  In May 2006 he was elected President in August 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 and 2017. He currently serves on the Management Advisory Committee.  Tim has attended conferences on water related issues.  He brings to the board a vast and wide range of expertise in water related issues.

Mr. Hildenbrand is a Certified Petroleum Geologist and has been involved in various aspects of the Oil and Gas industry since graduation in May of 1980.   Mr. Hildenbrand is currently employed by and is an officer with, the Zachry Group of Companies.  He has a B.S. in Geological Engineering and his education also includes an Intensive Spanish Course, Proyecto Linguistiso Francisco Maroquin Antigua, Guatemala, Central America.

Tim, his wife and their children live in the rural area of Medina County.  Tim is active in community affairs and is also a rancher.

Present Term August 2015-August 2018
Ms. Nentwich was appointed to the Board of Directors in October of 2004 to fill a vacancy in the 2003-2006 term. Ms. Nentwich was first elected as 1st Vice President in 2007 and currently serves as 1st Vice President in 2017.  She serves as Chair on the Wages and Benefits Committee and Finance Committee.  Caroline brings to the board 40 plus years of business administrative knowledge and skills.  She has attended numerous conferences on water related issues and also attended the Public Funds Investment  Training course.

Ms. Nentwich has been in the business sector for over 40 years primarily in the Information Systems arena within the Financial Industry.  Ms. Nentwich has a Bachelor's degree in accounting with a concentration in Business Data Systems and a MBA with a concentration in Information Systems.

Ms. Nentwich and her late husband Karl reside outside of Castroville.  They have two sons Karl and Brian.  Caroline and  is also a  rancher.

JONELL M. TARVIN, Secretary/Treasurer
Present Term August 2017- August 2020
Ms. Tarvin was elected to the Board of Directors in August 1999.   She was reelected in August 2002, August 2005, 2008, 2011, 2014 and again in August 2017. She has held the office of 2nd Vice-President and is current the Secretary/Treasurer. She serves as Chair of the Finance Committee and also serves on the Management Advisory Committee.  She has completed a course in Public Funds Investment in compliance with the Public Funds Investment Act.  She has attended a number of conferences and seminars on water issues.   She brings to the board a reliable expertise in management and finance.   

Ms. Tarvin is retired from Southwestern Bell Telephone Co., where she worked for 29 years as Area Manager.  She is also a certified substitute teacher.  

Ms. Tarvin and her late husband John raised their family in the Dunlay/Castroville area .  Mrs. Tarvin is active in community affairs and is a rancher. 

Present Term August 2016-August 2019
Mr. Sultenfuss was appointed to the Board of Directors in March 1993. He was elected to the board in August 1995, August 1998, August 2001, August 2004,  August 2007, 2010, 2013 and August 2016. Mr. Sultenfuss was appointed 2nd Vice President at the May 15, 2018 Board Meeting. Mr. Sultenfuss is Chair of the Operations Committee.  Richard brings to the board valuable knowledge of general operations of wells, pumps, and motors.    

Mr. Sultenfuss has an Associates Degree in Applied Science-Refrigeration, a class A Air Conditioning and Heating License, Water Analysis Training, and a Factory Chiller and Pumps certification, and is a licensed H/VAC Contractor. He has recently retired from the Assistant Manager of Mueller and Wilson Inc. in San Antonio.

He and his wife Cindy reside and raised their children in the rural area of the southeast section of Medina County.   He is active in community affairs and is also a rancher.  

Present Term 2017-2020
Mr. De La Fuente was Board appointed in May 2010 to serve the unexpired 2008-2011 term vacated by Domingo Rascon's resignation.  Mr. De La Fuente has been an East Medina customer for over 20 + years and has lived his entire life here. He is married and has 3 children and lives in the Devine area. Mr. De La Fuente is an active member with his church and community. He currently works for Chevon and had previously worked for Southwest Research for 17 years. His speciality is testing oil and additives. Mr. De La Fuente currently serves on the Wage and Benefits Committee.

Present Term 2015-2018
Mr. Tschirhart was Board appointed in November 2010 to serve the unexpired 2009-2012 term vacated by Donald W. Johnson's resignation. Mr. Tschirhart's father was one of the original members of East Medina County Water Supply Corporation. Mr. Tschirhart is currently retired but has many years of experience in the plumbing supply field. Mr. Tschirhart and his wife Linda live in the Devine area. Mr. Tschirhart currently serves on the Operations Committee.

Board of Directors Bios Board of Directors Bios

Relevant Documents