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At his first job as a civil engineer fresh out of college, Allen Peyser found himself inspecting sewer lines beneath the streets of Seattle, Washington by wading knee deep through miles of 54-inch pipe wearing rubber hip boots. In another realm, about that same time, computers were just coming on the scene. Peyser saw a groundfloor opportunity and embraced the newfangled machines, teaching himself to write code on a teletype that communicated with a mainframe computer.

You'd think the new kid on the engineering block would use his computer knowledge as a ticket out of the underground pipelines. But the funny thing is, Peyser actually loved working in sewers. Combining two opposite worlds, the smelly reality of wastewater and the comfort of exploring the digital domain from a keyboard, he developed Hydra, a computer program that models sewer systems. This proved a breakthrough, as wastewater consultants and city sewer managers have used his software for 30 years to analyze and design storm and sanitary systems.

A Seattle native, Peyser went to college at the University of Washington and earned bachelor's degrees in civil engineering and philosophy. The 68-year-old got his start in sewers in the mid-1960s as an employee at the City of Seattle Engineering Department, where he spent five years working in various departments. "I was very fortunate to do that. I went from structural to the construction division, and I became the soils engineer for the city," he recalls. His work in the structural department involved designing major trunk lines, a glorified name for large-diameter sewers, and unusual structures within those.

Looking back on how he serendipitously came to work with sewers (let's not say he fell into it), he reveals, "I suppose it was more by chance, but I loved everything about engineering, every aspect of it, and this was an opportunity for me to excel in one particular area. Computers were just starting, and in those days, they were not seriously looked at. I found that my skills on the computer plus this particular field seemed almost perfect."

After leaving the City of Seattle, Peyser moved on to become a project manager at CH2M Engineers in Seattle, an engineering firm known for sewer analysis and design. "In that capacity, I started working on sewers seriously," he states. At the time, using computers involved time-sharing on a teletype machine that communicated with a central processor. CH2M gave him a job to develop a comprehensive master plan for the city of Aurora, Colorado, a project that would involve calculating current and future flows for over 2000 existing pipes. Slide rules and tables were the normal approach in those days, but with this many calculations, Peyser saw it as an ideal application for a computer program.

CH2M had neither the budget nor the desire to develop a computer program to analyze sewer systems, but they agreed that if Peyser developed software for the project on his own time and paid for the computer time himself, the program would belong to him. He worked long hours and spent $3,000 on a portable terminal. Using a teletype with paper tape punch, he transmitted source code to a remote mainframe. The result: a program he dubbed Hydra. "It was very simplistic but very effective," he says. Working with only a technician on the Aurora project, "We were able to get it done way ahead of schedule and under budget, which was not typical in those days."

Peyser proved the effectiveness of Hydra on the Aurora job. "It could have been a disaster when the planning department gave me a completely different set of population figures near the end of the project," he explains. He was able to correct the population data and re-analyze the system in a matter of hours, marking the first known use of a model for this type of correction.

The city of Aurora was thrilled with Hydra's ability to quickly calculate estimated construction costs.
Near the end of the project, the city asked Peyser to analyze a scenario involving a major change in one area of the city. A developer had proposed a planned unit development for many blocks. City council wanted to approve it but first consulted the engineering department, who asked him what it would cost to service it. "I was able to complete that in one day and give them new calculations," Peyser reports. It would've cost about $80,000 in increased trunk sizes and pump stations. City council approved it provided the developer paid the $80,000, and the developer agreed. "The city engineer said this was the first time he'd been able to procure additional funds for a development because normally they couldn't react quickly enough on questions like this. So the study, which cost around $50,000, actually made a profit for the municipality."

"To my knowledge, this was the first comprehensive plan in the United States done in a model on a computer," Peyser continues. "The city got an extremely good comprehensive plan, very realistic, and they were able to adjust it by just changing a few numbers. I was thrilled with that, and as a result, I continued to improve the model."

As Peyser tells it, in those days, few engineers at CH2M had any interest in using the funny looking computer terminal in the office, and those that did had no one to teach them. "A few of us sat down, and we just ground through learning Basic language, reading books. It took a number of years to become a good programmer." He used Basic until Fortran came along, and he also used Pascal, which he has stuck with ever since (it's now called Delphi).

ISI, a time share firm CH2M used, supplied Peyser with a free terminal at home with the understanding they would have rights to market his programs. "They charged royalties on the program, and I was able to receive 50 percent of that. It turned out I was making as much or more on the computer program than I was with my salary at the engineering firm," he relates. "It was an exciting experience, an exciting period of time. And that was the start of the commercial Hydra."

With such success, word of Hydra began to spread in the industry. In 1973, Peyser left CH2M and made Hydra available via a time share service and later started Pizer, Inc., to market it. He continued to develop the program, incorporating suggestions from a growing base of consulting firms and municipal users in Washington, Oregon and Idaho. Royalties from Hydra kept Peyser equipped with the latest computer technology to allow him to continue development. He adapted Hydra to the IBM-PC in 1984, and he began to hire programming and administrative staff to help him keep up with the growing demands for the PC version of Hydra.

New features grew rapidly. In 1990, Hydra came to incorporate GISMaster, an AutoCAD add-on tool for digitizing sewer collection systems to define land use and sanitary service areas and storm water drainage basins. Released in 1993, HydraGraphics incorporated GIS technology as a stand-alone Windows application.

Today, Hydra sees use in a variety of projects that fall under the umbrella of municipal sewer management, including master planning, storm water management, infiltration and inflow studies, rehabilitation projects, elimination of overflows, and collection system design. It plays a crucial role in today's infrastructure, as many sewer systems are stressed by rapid growth and old age and face costly improvements.

A model of a sewer system allows officials to identify problem areas and find smarter, less costly ways to increase capacity of an existing system. Often, they can route added flows to another part of the system and stay under capacity. During rain storms, some cities experience overflows of wastewater into local streams or lakes, violating state or EPA regulations. A model of a collection system allows them to predict overflows and see how the system will react under different storm scenarios and test different solution options.

Peyser continues to work on improving Hydra, developing new Hydraulic modeling methods. His son Dale, a programmer, has taken over some of the work, and his daughter Cindy manages the business side of the company. "It's really a family company. We all know our jobs so well, we're quick at what we do, it works out very well," he says. He takes satisfaction in knowing his family will continue the business in the future. "It's just plain wonderful. It's a fun place to go. We get along so well."

Currently, the family spends much of its time working on a major upgrade known as Hydra 7. "It's a huge project, but I'm really excited about it and its potential," Peyser relates. He describes how it uses an analog instead of digital format. This means X-Y curves will replace steps, which can eat up computer time when you specify a short step length to yield a smooth curve plot. "In many cases, it saves enormous computer resources. This will break new ground for us."

It becomes obvious Peyser loves to talk about sewers, engineering, and his work. He has refined a practical seat-of-the-pants philosophy over the years. "In the area of sewers, it's much more an art than a science. That's what makes it so exciting. Sewer analysis is not rigid. You have to temper it with judgment," he espouses. "I like to think Hydra comes from the sewer up rather than from the academic side down." Looking to the future, he sees a new trend in systems that will operate in real time. "Computer simulation of a sewer system will be a continuous process."

Despite his age, Peyser wouldn't surprise many people if he stuck around long enough to have a hand in that. "Although I loved all kinds of civil engineering, this one just turned out to be the right one for me. Although I stumbled into it, I fell in love with it. Because I can't break away from it, I'll probably never retire."

Progressive Engineer
Editor: Tom Gibson
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570-568-8444 * progress@jdweb.com
©2004 Progressive Engineer