Exhibit 99.1 LOGO March 1, 2018 Mr. Josh Peterson San Juan Basin Royalty Trust Compass Bank, Trustee 2200 Post Oak Blvd.,
Floor 18 Houston, Texas 77056  Re:
Evaluation Summary San Juan Basin Royalty Trust Interests Proved Reserves As of December 31,
2017 Dear Mr. Peterson: As requested, we are submitting our estimates of proved
reserves and our forecasts of the resulting economics attributable to the above captioned interests. It is our understanding that the proved reserves estimated in this report constitute 100 percent of the proved reserves owned by the San Juan
Basin Royalty Trust, all of which are located in the San Juan Basin of northwestern New Mexico. Composite reserve estimates
and economic forecasts for the proved reserves are summarized below:  Proved ReservesDevelopedProducing


DevelopedNon-Producing


Undeveloped


TotalNet ReservesOil/Condensate


- Mbbl



256.7



0.6



0.0



257.3Gas


- MMcf



97,418.3



345.9



0.0



97,764.2RevenueOil/Condensate


- M$



9,672.6



21.3



0.0



9,693.9Gas


- M$



256,925.9



948.0



0.0



257,873.9Production Severance Tax


- M$



27,391.8



99.7



0.0



27,491.5Operating Expense


- M$



0.0



0.0



0.0



0.0Operating Income (BFIT)


- M$



239,206.6



869.6



0.0



240,076.2Discounted @ 10%


- M$



136,662.2



327.7



0.0



136,989.8 The discounted value shown above should not be construed to represent an estimate of the fair market
value by Cawley, Gillespie & Associates, Inc.




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Mr. Josh Peterson San Juan Basin Royalty Trust Interests March 1, 2018 Page
 2  As to the assumptions, methods and procedures used in connection with the preparation of
this report, prices were forecast in accordance with Securities and Exchange Commission guidelines using average annual prices of $2.98 per MMBtu (Henry Hub) and $51.34 per barrel (WTI Cushing). Gas price adjustments were specified by property with
values ranging from 0.50 to 1.37. The adjusted volume-weighted average gas price over the life of the properties is $2.62 per Mcf. The above oil price was adjusted for an overall differential of -$13.67 per barrel. Operating expenses and capital costs were based on an analysis of data provided by ConocoPhillips (on behalf of Burlington Resources
Oil & Gas Company LP) and Hilcorp Energy. Operating expenses include direct lease operating expenses and administrative overhead. Investments include drilling costs, work-over costs and production equipment costs. Severance taxes were
forecast as 10.3% of gas revenue and 9.6% of oil revenue. Neither expenses nor investments were escalated. The cost of plugging and the salvage value of equipment have not been considered. The proved reserve classifications conform to criteria of the Securities and Exchange Commission. The reserves and economics are
predicated on the regulatory agency classifications, rules, policies, laws, taxes and royalties in effect on the effective date except as noted herein. The possible effects of changes in legislation or other Federal or State restrictive actions have
not been considered. The reserves were estimated using a combination of the production performance, volumetric and analogy methods, in each case as we considered appropriate and necessary to establish the conclusions set forth herein. All reserve
estimates represent our best judgment based on data available at the time of preparation and assumptions as to future economic and regulatory conditions. Due to the inherent uncertainties of reserves estimates, it should be realized that the
reserves actually recovered, the revenue derived therefrom and the actual cost incurred could be more or less than the estimated amounts. The reserve estimates were based on interpretations of factual data furnished by ConocoPhillips, Hilcorp Energy and the San Juan Basin Royalty Trust. Liquid and gas price information, cost and expense
history, subject wells and ownership were supplied by ConocoPhillips and were accepted as furnished. To some extent, information from public records has been used to check and/or supplement these data. The basic engineering and geological data were
utilized subject to third party reservations and qualifications. Nothing has come to our attention, however, that would cause us to believe that we are not justified in relying on such data. An on-site
inspection of these properties has not been made nor have the wells been tested by Cawley, Gillespie & Associates, Inc. Our work-papers and related data are available for inspection and review by authorized parties. Respectfully submitted,  LOGO CAWLEY, GILLESPIE & ASSOCIATES, INC. Texas Registered Engineering Firm F-693