Patrick Murphy

Go to Projects then Dog Impacts

December 4, 2001

I am a plant ecologist, I have had three dogs in my life, I don’t hate dogs, I love dogs.

This presentation provides an update on the impacts of dogs on Sanitas Valley in City of Boulder Open Space. This update includes data, observations, and recommendations.

I have followed this topic for many years, including the original public meetings called the dog management roundtable. I was concerned that the plans for the management of dog impacts included only education and the establishment of rules of behavior, but did not include enforcement, fines or funding for the enforcement. I was hopeful that the educational approach along with peer-pressure, common sense and common courtesy would produce a harmonious solution. After many years and much effort, it has not succeeded in Sanitas Valley. Sanitas Valley is suffering long term severe impacts that will take a great deal of time and money to repair. The reasons that more restrictive dog regulations are justified and necessary are as follows:

The first graphic is the survey of dog feces on the Sanitas Valley trail. There were 1,492 piles of dog excrement along the trail and adjacent areas. What if there were 1,492 piles of human excrement in this area, would this be tolerated? I did not GPS survey the Dakota Ridge or Sanitas Ridge trails. The second graphic shows a detail near the trash can and bag dispenser. There were 38 piles within 50 feet and 148 piles within 100 feet of these facilities. One of the worst areas for dog excrement is at the beginning of the trail in a shady Chinese elm stand that could be a nice place for a picnic but is now a mess. Dogs love to defecate and urinate under trees along the trail. If you choose to rest in those shady spots how healthy do you suppose it is? Even if FIDOS or good intentioned citizens were to clean up every single pile of poop on a daily basis, the following impacts would not be avoided.

The areas with the most abundant dog feces are also severely trampled and have been aggressively invaded by jointed goatgrass, an introduced annual grass that is a State listed noxious weed. This grass grows to about 2.5 feet tall, dries out early in the spring, becomes a severe fire hazard, and has seeds that are perfect for distribution by dog fur. They are just a little sticky, and fall off easily. Four years ago there was only a small population of the grass at the foot of the trail. Now it is an almost continuous strip on the trail for half a mile and I found it on the trail to the top of Sanitas Ridge, about a mile and a half from the start of the trail. It occurs primarily in the dog-trampled areas with dog excrement.

There are abundant bare-soil compacted trails used solely by dogs that parallel the main trail and diverge from the main trail and lead to riparian areas, the irrigation ditch, and shrub clumps. Some of the shrub clumps have a dog path ringing the shrub. These trails are not only evidence of wildlife habitat invasion and destruction but also accelerate erosion. There used to be Towhees rustling in the shrubs that I could hear whenever I ran the trail, I don’t see or hear them now.

The lower end of Sanitas Valley with the highest density of dog excrement drains directly into the stormwater system that leads directly to Boulder Creek. The third graphic (see below and click here for the source) shows the fecal coliform counts for Boulder Creek at Eben G. Fine Park, 30^th Street, the Water treatment plant, and the confluence with Dry Creek. Some of the sites have data for high flow in June and low flow in October. The Colorado Department of Health and EPA Standard for swimming waters is also shown. The segment of Boulder Creek below Eben G. Fine Park exceeds the acceptable swimming water standard sometime after June and eventually exceeds the standard by almost 350% in October. It is highly likely that the standard is exceeded during the high utilization periods of July and August. Although there are many likely contributors to this problem, such as pigeons, raccoons, and cats, dogs are most likely the single biggest contributors.

For example there were 36 piles on the short stretch of trail between the north side of Boulder Creek and the Justice Center on July 15, 2001. The actual combined water quality degradation from the entire city must be huge, and the contribution from the irresponsible dog owners on Open Space trails is undoubtedly making it much worse.

The fourth item in the packet is a nationwide study of the water quality issue, so you can put this all into perspective at some other time, but please look at page 76. This is to demonstrate that dog excrement is not less of a health risk when compared to human excrement. Note that a dog feces has almost twice the fecal coliform content and more than 100 times the fecal streptococci content in comparison with human feces.

What have I learned from my observations, as well as data collection, over the last few years of dealing with the dog management issue?

1. Dogs off-leash are destructive non-passive recreational use of Open Space. Leash-only areas have impacts that are just as severe but closer to the trails.
2. Only 1 out of 20 dogs are truly under voice and sight control in off-leash areas. I have seen hundreds of instances where the dog lags behind the owner, leaves a poop that the owner does not, or pretends not to see, and the owner still considers their dog to be under voice and sight control.
3. A large, rather than small, percentage of dog owners are irresponsible, and most irresponsible dog owners consider themselves perfectly responsible. Since only 1 out of 5 dogs in Boulder is licensed, there are data to validate this perception.
4. Many if not most dog owners have very little understanding of the negative impacts of their dog, and are not likely to be affected by educational efforts without enforcement.
5. The percentage, or ratio, of responsible to irresponsible dog owners is absolutely irrelevant when total net impacts result in destruction or serious degradation of the natural resource. If you want to measure impacts, measure the impacts, not what percentage of the population is causing the impacts. If the impacts are real and serious and costly to repair who cares if only .01% or 60% of the population is responsible. The percentage is not the critical measure, the impacts are.
6. The FIDOS organization and many dog owners are in denial about the negative impacts of dogs. They seem to believe that good intention and superficial appearance are more important than bottom line results. They also seem to believe that the only way to prove that dogs have negative impacts is to let an area become so degraded that they can then continue to have dog access because the area is already degraded!
7. Dog owners have disproportionate negative impacts and access on Open Space. Dog owners are only about 25% of the population. Once negative impacts due to irresponsible dog owners has been documented in an area, and shown to be costly to repair, the privilege of dog access should be revoked until repairs are completed, and management protocol can be reevaluated and modified.
8. More areas need to be available as dog-free.
9. Off-leash dog parks are needed and should only be located in non-native vegetation areas. These areas are going to be high maintenance as shown by the dog parks in Boulder that have been trampled to dirt. Some sort of rotation of off-leash areas, allowing a recovery period after a certain level of degradation has been reached, would be one way to handle the heavy impacts.
10. There are an unlimited number of excuses, diversions, and exceptions that the irresponsible dog owners will use to rationalize their actions. Enforcement, fines, and funding for the enforcement are parts of the educational process that have to be instituted and sustained. If the land manager cannot afford the enforcement that is necessary, then dogs should be banned.

Leather (1994) points out that dog bans are spreading in Europe because of enforcement difficulties and because of lack of co-operation from dogs owners in acknowledging their responsibilities. The same trend would seem to be occurring here, although unevenly. It is this response which is of most concern - not if it is imposed with good reason in a particular park - but if it is imposed in all or most of the public spaces available at the local level or if it is imposed for no apparent good reason.

Leather, K. L. (1994) 'Legislation for Urban Animal Management : Experience in the Formulation and Implementation of Scoop Law' in Paxton, D.W (ed.) Urban Animal Management, Proceedings of the Third National Conference on Urban Animal Management in Australia, Canberra, 1994, Australian Veterinary Association

So many dog owners have abused the off-leash privilege in Sanitas Valley, that there are now many good reasons to ban dogs. It would have been better to never let it get to this point. It is time to acknowledge the damage done by dogs and learn from the lesson of Sanitas Valley where the true colors of many dog owners have been revealed and the destructive results of their actions are evident and getting worse.

Water Quality in Boulder Creek

@Ebin G. Fine

@ 30^th Street
June, 2000 170

@ Waste Water treatment Plant

@Dry Creek Confluence