Routley responds to DC water system report
J. Gordon RoutleySome of you may have read the reports we showed you 10 days ago looking into the fire on Adams Mill Road and concerns about small diameter water mains in the District of Columbia. It was hard not to notice that the two reports, one from DC Fire & EMS (DCFEMS) and the other from the DC Water & Sewer Authority (WASA), came up with very different conclusions.
The headline from the DCFEMS report is that the water system infrastructure in the Nation’s Capital is “highly questionable”. The WASA report indicated only one real problem area effecting a developed part of the city.
Trying to get to the bottom of how these reports could be so far apart, we have tried to ask further questions of DCFEMS, WASA and those involved in the report. The only response we have received is from J. Gordon Routley, a former fire chief and an experienced consultant in fire service matters.
According to the DCFEMS report, Routley supervised the testing of hydrants around the Adams Mill Road building. He also looked at the city’s water system from a more general standpoint. Below is Chief Routley’s response to my efforts to get a better understanding why there was such a difference of opinion:
My comments are in reference to the study that was released by WASA on fire flow in areas with small diameter mains. This was done in response to the WASA Board’s directive from October 5 to do a study and report back in 30 days…well, I guess they did the best they could do in 30 days with the data that was already in their computers.
The weaknesses with that analysis are:
1. The analysis is entirely theoretical, based on computer modelling of the water system. No actual flow tests were conducted to validate the calculations. There are lots of potential reasons why the real flow might not match the calculations…undetected closed valves…old water mains obstructed by tuberculation…underground leaks. It is all just theory until someone goes out and validates the analysis (systematically — neighborhood by neighborhood).
2. The analysis calculated the volume of water that is theoretically available in the underground mains at each “node” in the system. A node is a connection point in the computer model, generally representing the intersection of two sections of underground pipe. The hydrants are not incorporated into the model, so there is no assurance that there are hydrants available at/near the node locations or that the calculated flow can be obtained through those hydrants. For example, the model may indicate that the water mains can deliver 3000 gpm to a certain location in the underground system. If there is no hydrant at that location, the fire department can’t obtain that water. If there is one hydrant at that location, the maximum flow available to the fire department is the maximum flow through the hydrant …which is generally around 1500 gpm…2000 gpm under the best circumstances. The FD needs at least two hydrants (connected to the right underground mains) to obtain 3000 gpm.
3. The analysis assumes that everything is OK if the needed fire flow (based on the size, occupancy and construction of the building and its exposures) is available at a node within 1000 feet of the location. If there is no hydrant…or no road that allows fire apparatus to get to the hydrant from the fire…that’s not OK. It’s also a problem if the hydrant is not working.
4. The analysis only considered needed fire flows up to 2000 gpm. They considered buildings/locations that require more than 2000 gpm as special cases that require individual analysis.
Areas that may require the water system to have a greater fire flow capacity (3,000 gpm or greater) associated with larger diameter water mains need further investigation, through a coordinated effort with FEMS and is not included as part of the scope of this analysis.
There is a logic disconnect when they assume that the maximum you should expect small main systems to deliver is 2000 gpm, so the analysis only looked at flows up to 2000 gpm. What about areas that have small mains where the needed fire flow is greater than 2000 gpm?
This whole discussion started with the fire on Adams Mill Road in a building with a needed fire flow of 2500 gpm. The mains within that neighborhood are small, old and appear to be restricted. There are several buildings in that area (deeper into the neighborhood and more than 1000 feet from Columbia Road) with needed fire flows in the 3000 to 3500 gpm range.
If we look around DC as a whole, we will find numerous locations where the existing buildings have needed fire flows in the 2500 to 3500 gpm range. How many of those areas have small mains with limited flows? And how many years will it take to correct those deficiencies if/when they are identified?
5. The water system “requirements” are benchmarked against policies and practices in a lot of places that don’t look much like DC. They used a DC land use map and assigned estimates of needed fire flow based on the land use classifications. They did not calculate needed flows for any real buildings or obtain needed fire flows from DCFD or ISO. The analysis should be based on the real buildings that exist in each area of DC today. The data for hundreds (probably thousands) of buildings is available from ISO.
6. As noted in their analysis, there is no legally adopted code that requires WASA to provide any specific flow for firefighting purposes at any location. A city’s insurance grading is partially based on ISO’s evaluation of the ability of the water system to deliver the needed fire flow to each location in their jurisdiction. If they can’t deliver, the insurance grading is negatively impacted, but there is no legal code that requires WASA to provide the needed fire flow.
The study is interesting, but far from comprehensive.
If we go back to the Adams Mill incident, there is no question that the volume of water that was needed to fight the fire was not available from the hydrants in the immediately surrounding area. When that was discovered, DCFD had to go looking for more water, but the information that DCFD had available from WASA did not indicate where to go. All of the hydrants look the same, so how is DCFD supposed to know which ones are connected to large underground mains and which ones are connected to the same system of small mains that is already delivering it’s capacity? The maps that WASA provided to DCFD were impossible to interpret (I tried myself, in an office with good lighting and no urgency. I could only interpret about half of the information.)
As it turns out, there were three hydrants in the area that could have supplied the volume of water that was required….3 among a couple of dozen. DCFD connected to two of them, without the benefit of markings or good maps. If they had known, they could have obtained more water from those two hydrants or connected to the third —- BUT the guy that WASA sent to the scene to assist DCFD told them that they wouldn’t be able to get more water from the mains on Columbia Road and he suggested going to Connecticut Avenue. (everyone wants to overlook that little detail).
