An open letter to Williams Kuebelbeck & Associates

May 30 1999

Williams Kuebelbeck & Associates is the Marina Consultant for the "Marina Plan and Waterfront Overview" planning process. Their recommendation for the reconstruction of docks A,B,C,D & E calls for increasing the average slip length from 28.9 ft to 41 ft, and increasing berth fees to $6.00/ft/month.

This note is regarding the memoranda of March 17 and May 19, 1999, from Larry Williams of Williams Kuebelbeck & Associates, concerning increased marina revenue resulting from the rebuilding and reconfiguration of docks A through E.

I agree with the essential conclusion of the memos, but there are several technical points and several elements of "social engineering" that I believe have been neglected by Williams Kuebelbeck.

These are details, but details that could prove disastrous when it comes time to generate consensus among the marina community for proceeding with the project. Let's see if we can get them ironed out now.


The berth rate comparison table:

Berth rates shown for Berkeley and other municipal marinas need to be increased to reflect possessory interest tax, which is not paid by berthers at private marinas. This is on the order of $0.15 per foot per month.

Navigation draft:

Marketability of the Berkeley Marina is very poor for boats that draw more than 7 feet, and the situation is likely to become worse in the future. This will remain the case even after marina dredging, due to the extensive shoal areas outside the harbor extending well beyond the limits of any practical dredging project. This does not affect powerboats, but the Berkeley Marina environment is far more desirable for sailboats and these will continue to be the core market segment.

Revenue calculation: If the average size of a berth in the rebuilt docks is 41 feet, and the market value of a 41 foot berth is $6.00/ft, that does not mean that this is the average market value of all the berths. It only applies to that size. Larger berths might be worth more, smaller berths are certainly worth less on the current market. The revenue depends on the size distribution and the pricing structure, and I don't think we can assume a linear relationship between berth size and price.

Revenue/size calculation:

Berths take up area, not length, and the marina area is fixed. This means that more linear feet of small berths than large berths can be built in an existing marina. There are also fixed costs associated with each berth, which argues in favor of fewer berths of large size. But the net result of these two effects has not been analyzed rigorously - at lest not in any information made available to the Marina Plan Subcommittee at this time.


Who does the marina serve? The Berkeley Marina has other goals and objectives in addition to generating revenue. If part of the marina is re-designed to accommodate predominantly larger and more expensive boats, there will necessarily be a shift in the demographics of the owners. Specifically, the average income of the average boat owner will become much higher.

The cost of acquiring and maintaining a boat is a very strong function of its size. My data indicates that it varies by the length to at least the 3.5 power. That is, if you double the size, the costs all go up by a factor of at least eleven. One way to explain this is that boats are essentially sold by the pound. That would lead to an exponent of 3.0, assuming geometric similitude (a valid assumption for boats of similar type). However, a pound of big boat tends to cost more than a pound of small boat, for reasons that need not be explained here. So the exponent is greater than three. Other surveys of the used boat market have found the price/size exponent to be closer to 3.7.

Maintenance costs generally follow a fixed percentage of new replacement value, so they vary by about the same exponent.

Some examples: A typical 22 ft sailboat might be worth about $4,000. A 44 ft. sailboat of similar type, age, and condition might be worth about $45,000. A 66 ft boat might cost $187,000. (These numbers probably seem high for the 22 ft boat and low for the larger boats, because the exponent of 3.5 is conservative - it's really a little higher, for most types of boats and through most of the size range we're concerned with.) The result of this is that at $5.00 per foot, the 22 ft boat pays fully one-third of its value in berth fees every year. But the 44 ft boat pays six per cent of its value every year. The 66 ft boat pays only two per cent of its value every year.

Which group of boat owners is more likely to make a location decision based on price? The small boat owners, of course. For them it's a big part of the cost of owning the boat. For the big boat owner, it's lost in the noise, and the decision to berth in Berkeley or elsewhere is driven entirely by other factors.

From the point of view of marina planners, this means that the market will support a highly progressive rate structure. Bigger boats will pay much higher rates, but it will be difficult to attract new berthers to the smaller berths if the rates are significantly increased.

This suggests that the dock reconfiguration should emphasize the bigger berths, as recommended by Larry Williams. But this also implies a dramatic shift in the average value of the boats in these berths, and a corresponding shift in the demographics of the average berther. Increasing average berth size on docks A-E from the current 28.9 feet to the proposed 41 feet will mean that the value of the average size boat increases by a factor of about 3.4. If we assume that berthers spend a constant percentage of their income on their boats regardless of income (probably not an entirely valid assumption, but you get the idea) then we're shifting our average berther's income up by a factor of 3.4.

The marina currently contains a lot of small and "low value" boats owned by grad students, recent graduates, and local non-professionals. Do we want people in these demographic categories to continue to be able to buy a small boat and berth it here in Berkeley?

If demographic diversity is of any importance, if serving Berkeley residents is of any importance, then it's essential to include an ample supply of smaller berths in the rebuild plan.

This is not the same as catering to boats that are of low value due to poor condition and neglect, as is the case with some larger boats that are little more than derelicts. Because both the value and the normal operating costs of a boat are such a strong function of size, it's reasonable to conclude that any owner who claims inability to maintain their boat in reasonable operating condition due to economic constraints has a boat that is too big. I don't think we mind seeing the non-operable larger boats forced out due to higher rates. But we do mind seeing well-maintained small boats being forced out - or not able to afford access in the first place - because there are no berths available in that size range at a reasonable price.

Also note that this is not an argument for maintaining 20 ft. berths. Vacancy statistics seem to show that demand for this size is declining. But it is an argument for building new small berths in the lowest size categories for which demand is still strong.


The revenue calculations by Willimas-Kuebelbeck assume that the marina will introduce a two-tiered rate structure, charging more for the new berths on docks A-E than for existing berths of similar or perhaps greater desirability. But the existing berths on the south side of the marina will continue to have better access to the yacht club, the best restaurant, and the Cal Sailing Club's crew pool. It's hard to imagine proximity to Chavez Park on the north side being seen as a desirable feature - in fact it might be a significant negative factor, from the point of view of the owner of a large yacht. Consider parking loads during peak summer weekends as the popularity of the park increases, especially during events like the annual kite festival.

A two-tiered rate structure will not be transparent to the berthers. It's hard to see how it can be justified to the Berther's Association, and their activism is often motivated by a strong sense of fairness. Berthers on the new docks will all want to be on the waiting list for more economical berths on the other docks, reducing availability of those docks to new berthers and increasing administrative workload.


The plan for rebuilding and reconfiguring docks A through E, and the associated economic analysis, should be modified as follows:

1) Show your work.

We don't have a clear comparison of the various berth size options in terms of berths per square foot of marina. That is, if the berths are re-built at a smaller average size but using the same density guidelines and water use area as proposed, how many more linear feet could be accommodated? Several variables (water use area, average berth size, and a rate differential with respect to the remainder of the marina) are being changed simultaneously in the economic analysis. We need to see the effect of each one individually in order to decide which ones we want to adopt. Also, we don't see the estimates of fixed overhead cost per berth, or the effect of berth size on parking load. (Note that boats carry crew or guests roughly in proportion to the square of their size, especially for short-duration trips on summer weekends when parking is most likely to be at capacity.)

Perhaps your experience with marina design is such that you can confidently internalize some of these factors, rather than perform a rigorous analysis, and still produce a reliable result. However, this needs to be stated if this is the case. Subjective evaluation is usually based on experience, but some of this basis might not be transferable from previous marina projects to Berkeley.

2) Propose a consistent rate structure.

My opinion is that the two-tiered rate structure simply will not fly. But I also agree that there is considerable room to generate more revenue, not just from new berths but from the entire marina, given a realistic and progressive rate structure and some improvement in basic amenities. Please see the proposal on my web page at for more details about rate structure.

The recommendations and economic analysis should reflect a new but consistent rate structure for the entire marina.

Thank you for your attention to these comments